OS Definition

Windows 2000

2010-08-14T01:33:00.000-07:00

Windows 2000

Windows 2000 is a line of operating systems produced by Microsoft for use on business desktops, notebook computers, and servers. Released on February 17, 2000, it was the successor to Windows NT 4.0, and is the final release of Microsoft Windows to display the "Windows NT" designation. It was succeeded by Windows XP for desktop systems in October 2001 and Windows Server 2003 for servers in April 2003.

Four editions of Windows 2000 were released: Professional, Server, Advanced Server, and Datacenter Server. Additionally, Microsoft sold Windows 2000 Advanced Server Limited Edition and Windows 2000 Datacenter Server Limited Edition, which were released in 2001 and run on 64-bit Intel Itanium microprocessors. While each edition of Windows 2000 was targeted to a different market, they share a core set of features, including many system utilities such as the Microsoft Management Console and standard system administration applications. Support for people with disabilities has been improved over Windows NT 4.0 with a number of new assistive technologies,and Microsoft increased support for different languages and locale information. All versions of the operating system support the Windows NT filesystem, NTFS 3.0, the Encrypting File System, as well as basic and dynamic disk storage The Windows 2000 Server family has additional features, including the ability to provide Active Directory services (a hierarchical framework of resources), Distributed File System (a file system that supports sharing of files) and fault-redundant storage volumes. Windows 2000 can be installed through either a manual or unattended installation. Unattended installations rely on the use of answer files to fill in installation information, and can be performed through a bootable CD using Microsoft Systems Management Server, by the System Preparation Tool.

Microsoft marketed Windows 2000 as the most secure Windows version ever, but it became the target of a number of high-profile virus attacks such as Code Red and Nimda Over nine years after its release, it continues to receive patches for security vulnerabilities nearly every month.

History:

Windows 2000 is a continuation of the Microsoft Windows NT family of operating systems, replacing Windows NT 4.0. Originally called Windows NT 5.0, then Windows NT 2000, Microsoft changed the name to Windows 2000 on 27 October 1998. It is also the first Windows version that has been released without a code name, though Windows 2000 Service Pack 1 was codenamed "Asteroid" and Windows 2000 64-bit was codenamed "Janus" (not to be confused with Windows 3.1, which had the same codename). The first beta for Windows 2000 was released in September 1997 and several further betas followed until Beta 3 which was released on 29 April 1999. During the development, there was a DEC Alpha build of Windows 2000 but it was abandoned with the second beta. From here, Microsoft issued three release candidates between July and November 1999, and finally released the operating system to partners on 12 December 1999. The public could buy the full version of Windows 2000 on 17 February 2000. Three days before this event, which Microsoft advertised as "a standard in reliability", a leaked memo from Microsoft reported on by Mary Jo Foley revealed that Windows 2000 had "over 63,000 potential known defects".After Foley's article was published, Microsoft blacklisted her for a considerable time: InformationWeek summarized the release "our tests show the successor to NT 4.0 is everything we hoped it would be. Of course, it isn't perfect either." Wired News later described the results of the February launch as "lackluster". Novell criticized Microsoft's Active Directory, the new directory service architecture as less scalable or reliable than its own Novell Directory Services (NDS) alternative. Windows 2000 was first planned to replace both Windows 98 and Windows NT 4.0. However, that changed later. Instead, an updated version of Windows 98 called Windows 98 Second Edition was released in 1999 and Windows Me was released in late 2000. Close to the release of Windows 2000 Service Pack 1, Microsoft released Windows 2000 Datacenter Server, targeted at large-scale computing systems with support for 32 processors, on 29 September 2000.

On or shortly before 12 February 2004, "portions of the Microsoft Windows 2000 and Windows NT 4.0 source code were illegally made available on the Internet". The source of the leak remains unannounced. Microsoft issued the following statement:

"Microsoft source code is both copyrighted and protected as a trade secret. As such, it is illegal to post it, make it available to others, download it or use it."

Despite the warnings, the archive containing the leaked code spread widely on the file-sharing networks. On 16 February 2004, an exploit "allegedly discovered by an individual studying the leaked source code" for certain versions of Microsoft Internet Explorer was reported.

New and updated features:

Windows 2000 introduced many of the new features of Windows 98 and Windows 98 SE into the NT line, such as the Windows Desktop Update, Internet Explorer 5, Outlook Express, NetMeeting, FAT32 support, Windows Driver Model, Internet Connection Sharing, Windows Media Player, WebDAV support etc. Certain new features are common across all editions of Windows 2000, among them NTFS 3.0, the Microsoft Management Console (MMC), Automated System Recovery, UDF support, the Encrypting File System (EFS),Logical Disk Manager, Logical Disk Manager,support for PostScript 3-based printers, OpenType (.OTF) and Type 1 PostScript (.PFB) font support, the Data protection API (DPAPI), an LDAP/Active Directory-enabled Address Book, usability enhancements and multi-language and locale support. Windows 2000 also comes with several system utilities. Microsoft also introduced a new feature to protect critical system files, called Windows File Protection. This protects critical Windows system files by preventing programs other than Microsoft's operating system update mechanisms such as the Package Installer, Windows Installer and other update components from modifying them Microsoft recognized that a serious error or a stop error could cause problems for servers that needed to be constantly running and so provided a system setting that would allow the server to automatically reboot when a stop error occurred. Also included is an option to dump any of the first 64 KB of memory to disk (the smallest amount of memory that is useful for debugging purposes, also known as a minidump), a dump of only the kernel's memory, or a dump of the entire contents of memory to disk, as well as write that this event happened to the Windows 2000 event log. In order to improve performance on servers running Windows 2000, Microsoft gave administrators the choice of optimizing the operating system's memory and processor usage patterns for background services or for applications. Windows 2000 also introduced core system administration and management features as the Windows Installer, Windows Management Instrumentation and Event Tracing for Windows (ETW) nto the operating system.

Windows Explorer:

Windows Explorer has been enhanced in several ways in Windows 2000. It is the first Windows NT release to include Active Desktop, first introduced as a part of Internet Explorer 4.0 (specifically Windows Desktop Update), and only pre-installed in Windows 98 by that time It allowed users to customize the way folders look and behave by using HTML templates, having the file extension HTT. This feature was abused by computer viruses that employed malicious scripts, Java applets, or ActiveX controls in folder template files as their infection vector. Two such viruses are VBS/Roor-C and VBS.Redlof.a. The "Web-style" folders view, with the left Explorer pane displaying details for the object currently selected, is turned on by default in Windows 2000. For certain file types, such as pictures and media files, the preview is also displayed in the left pane. Until the dedicated interactive preview pane appeared in Windows Vista, Windows 2000 had been the only Windows release to feature an interactive media player as the previewer for sound and video files. However, such a previewer can be enabled in Windows Me and Windows XP through the use of third-party shell extensions, as the updated Windows Explorer allows for custom thumbnail previewers and tooltip handlers. The default file tooltip displays file title, author, subject and comments; this metadata may be read from a special NTFS stream, if the file is on an NTFS volume, or from an OLE structured storage stream, if the file is a structured storage document. All Microsoft Office documents since Office 95 make use of structured storage, so their metadata is displayable in the Windows 2000 Explorer default tooltip. File shortcuts can also store comments which are displayed as a tooltip when the mouse hovers over the shortcut.

The right pane of Windows 2000 Explorer, which usually just lists files and folders, can also be customized. For example, the contents of the system folders aren't displayed by default, instead showing in the right pane a warning to the user that modifying the contents of the system folders could harm their computer. It's possible to define additional Explorer panes by using DIV elements in folder template files Other Explorer UI elements that can be customized include columns in "Details" view, icon overlays, and search providers: the new DHTML-based search pane is integrated into Windows 2000 Explorer, unlike the separate search dialog found in all previous Explorer versions. This degree of customizability is new to Windows 2000; neither Windows 98 nor the Desktop Update could provide it. The Indexing Service has also been integrated into the operating system and the search pane built into Explorer allows searching files indexed by its database.

NTFS 3.0:

Microsoft released the version 3.0 of NTFS (sometimes incorrectly called NTFS 5 in relation to the kernel version number) as part of Windows 2000; this introduced disk quotas (provided by QuotaAdvisor), file-system-level encryption, sparse files and reparse points. Sparse files allow for the efficient storage of data sets that are very large yet contain many areas that only have zeros. Reparse points allow the object manager to reset a file namespace lookup and let file system drivers implement changed functionality in a transparent manner. Reparse points are used to implement volume mount points, junctions, Hierarchical Storage Management, Native Structured Storage and Single Instance Storage Volume mount points and directory junctions allow for a file to be transparently referred from one file or directory location to another.

Encrypting File System:

The Encrypting File System (EFS) introduced strong file system-level encryption to Windows. It allows any folder or drive on an NTFS volume to be encrypted transparently by the user.EFS works together with the EFS service, Microsoft's CryptoAPI and the EFS File System Runtime Library (FSRTL). To date, its encryption has not been compromised.

EFS works by encrypting a file with a bulk symmetric key (also known as the File Encryption Key, or FEK), which is used because it takes less time to encrypt and decrypt large amounts of data than if an asymmetric key cipher were used The symmetric key used to encrypt the file is then encrypted with a public key associated with the user who encrypted the file, and this encrypted data is stored in the header of the encrypted file. To decrypt the file, the file system uses the private key of the user to decrypt the symmetric key stored in the file header. It then uses the symmetric key to decrypt the file. Because this is done at the file system level, it is transparent to the user. For a user losing access to their key, support for recovery agents that can decrypt files is built in to EFS. A Recovery Agent is a user who is authorized by a public key recovery certificate to decrypt files belonging to other users using a special private key. By default, local administrators are recovery agents however they can be customized using Group Policy.

Basic and dynamic disk storage:

Windows 2000 introduced the Logical Disk Manager for dynamic storage All versions of Windows 2000 support three types of dynamic disk volumes (along with basic disks) : simple volumes, spanned volumes and striped volumes:

* Simple volume, a volume with disk space from one disk.

* Spanned volumes, where up to 32 disks show up as one, increasing it in size but not enhancing performance. When one disk fails, the array is destroyed. Some data may be recoverable. This corresponds to JBOD and not to RAID-1.

* Striped volumes, also known as RAID-0, store all their data across several disks in stripes. This allows better performance because disk reads and

Accessibility:

Microsoft increased the usability of Windows 2000 over Windows NT 4.0 for people with visual and auditory impairments and other disabilities. They included several utilities designed to make the system more accessible,

although many of these features were already available with previous versions of Windows:

* FilterKeys: a group of keyboard-related features for people with typing issues, including:

o SlowKeys: Ignore any keystroke not held down for a certain period.

o BounceKeys: Ignore repeated keystrokes pressed in quick succession.

o RepeatKeys: lets users slow down the rate at which keys are repeated via the keyboard's key-repeat feature.

* ToggleKeys: when turned on, Windows will play a sound when the CAPS LOCK, NUM LOCK or SCROLL LOCK key is pressed.

* MouseKeys: lets users move the cursor around the screen via the numeric keypad.

* On-screen keyboard: displays a virtual keyboard on the screen and allows users to press its keys using a mouse or a joystick.

* SerialKeys: lets Windows 2000 support speech augmentation devices.

* StickyKeys: makes modifier keys (ALT, CTRL and SHIFT) become "sticky": a user can press the modifier key, and then release it before pressing the combination key. (Activated by pressing Shift five times quickly.)

* Microsoft Magnifier: A screen magnifier that enlarges a part of the screen the cursor is over.

* Microsoft Narrator: Introduced in Windows 2000, this is a screen reader that utilizes the Speech API.

* High contrast theme: to assist users with visual impairments.

* SoundSentry: designed to help users with auditory impairments, Windows 2000 shows a visual effect when a sound is played through the sound system.

Languages and locales:

Windows 2000 introduced the Multilingual User Interface (MUI). Besides English, Windows 2000 incorporates support for Arabic, Armenian, Baltic, Central European, Cyrillic, Georgian, Greek, Hebrew, Indic, Japanese, Korean, Simplified Chinese, Thai, Traditional Chinese, Turkic, Vietnamese and Western European languages It also has support for many different locales

Games:

Windows 2000 included version 7.0 of the DirectX API, commonly used by game developers on Windows 98. The last version of DirectX that Windows 2000 supports is DirectX 9.0c (Shader Model 3.0), that shipped with Windows XP Service Pack 2. Currently, Microsoft publishes quarterly updates to DirectX 9.0c; these updates contain bug fixes to the core runtime and some additional libraries such as D3DX, XAudio 2, XInput and Managed DirectX components. The majority of games written for recent versions of DirectX can therefore run on Windows 2000.

System utilities:

Windows 2000 introduced the Microsoft Management Console (MMC), which is used to create, save, and open administrative tools Each of these is called a console, and most allow an administrator to administer other Windows 2000 computers from one centralised computer. Each console can contain one or many specific administrative tools, called snap-ins. These can be either standalone (with one function), or an extension (adding functions to an existing snap-in). In order to provide the ability to control what snap-ins can be seen in a console, the MMC allows consoles to be created in author mode or user mode. Author mode allows snap-ins to be added, new windows to be created, all portions of the console tree to be displayed and consoles to be saved. User mode allows consoles to be distributed with restrictions applied. User mode consoles can grant full access to the user for any change, or they can grant limited access, preventing users from adding snapins to the console though they can view multiple windows in a console. Alternatively users can be granted limited access, preventing them from adding to the console and stopping them from viewing multiple windows in a single console

The main tools that come with Windows 2000 can be found in the Computer Management console (in Administrative Tools in the Control Panel). This contains the Event Viewer—a means of seeing events and the Windows equivalent of a log file a system information utility, a backup utility, Task Scheduler and management consoles to view open shared folders and shared folder sessions, configure and manage COM+ applications, configure Group Policy, manage all the local users and user groups, and a device manager. It contains Disk Management and Removable Storage snap-ins, a disk defragmenter as well as a performance diagnostic console, which displays graphs of system performance and configures data logs and alerts. It also contains a service configuration console, which allows users to view all installed services and to stop and start them, as well as configure what those services should do when the computer starts.

Windows 2000 comes with two utilities to edit the Windows registry, REGEDIT.EXE and REGEDT32.EXE. REGEDIT has been directly ported from Windows 98, and therefore does not support editing registry permissions. REGEDT32 has the older multiple document interface (MDI) and can edit registry permissions in the same manner that Windows NT's REGEDT32 program could. REGEDIT has a left-side tree view of the Windows registry, lists all loaded hives and represents the three components of a value (its name, type, and data) as separate columns of a table. REGEDT32 has a left-side tree view, but each hive has its own window, so the tree displays only keys and it represents values as a list of strings. REGEDIT supports right-clicking of entries in a tree view to adjust properties and other settings. REGEDT32 requires all actions to be performed from the top menu bar. Windows XP is the first system to integrate these two programs into a single utility, adopting the REGEDIT behavior with the additional NT features

The System File Checker (SFC) also comes with Windows 2000. It is a command line utility that scans system files and verifies whether they were signed by Microsoft and works in conjunction with the Windows File Protection mechanism. It can also repopulate and repair all the files in the Dllcache folder

Recovery Console:

The Recovery Console is run from outside the installed copy of Windows to perform maintenance tasks that can neither be run from within it nor feasibly be run from another computer or copy of Windows 2000. It is usually used to recover the system from problems that cause booting to fail, which would render other tools useless.

It has a simple command line interface, used to check and repair the hard drive(s) , repair boot information (including NTLDR) , replace corrupted system files with fresh copies from the CD, or enable/disable services and drivers for the next boot.

The console can be accessed in either of the two ways:

1. Booting from the Windows 2000 CD, and choosing to start the Recovery Console from the CD itself instead of continuing with setup. The Recovery Console is accessible as long as the installation CD is available.

2. Preinstalling the Recovery Console on the hard disk as a startup option in Boot.ini, via WinNT32.exe, with the /cmdcons switch. In this case, it can only be started as long as NTLDR can boot from the system partition

Server family features:

The Windows 2000 server family consists of Windows 2000 Server, Windows 2000 Advanced Server, and Windows 2000 Datacenter Server.

All editions of Windows 2000 Server have the following services and features built in:

* Routing and Remote Access Service (RRAS) support, facilitating dial-up and VPN connections, support for RADIUS authentication, network connection sharing, Network Address Translation, unicast and multicast routing schemes.

* DNS server, including support for Dynamic DNS. Active Directory relies heavily on DNS.

* IPsec support and TCP/IP filtering

* Smart card support

* Microsoft Connection Manager Administration Kit (CMAK) and Connection Point Services

* Support for distributed file systems (DFS)

* Hierarchical Storage Management support including remote storage, a service that runs with NTFS and automatically transfers files that are not used for some time to less expensive storage media

* Fault tolerant volumes, namely Mirrored and RAID-5

* Group Policy (part of Active Directory)

* IntelliMirror, a collection of technologies for fine-grained management of Windows 2000 Professional clients that duplicates users' data, applications, files, and settings in a centralized location on the network. IntelliMirror employs technologies such as Group Policy, Windows Installer, Roaming profiles, Folder Redirection, Offline Files (also known as Client Side Caching or CSC), File Replication Service (FRS), Remote Installation Services (RIS) to address desktop management scenarios such as user data management, user settings management, software installation and maintenance.

* COM+ and MTS

* MSMQ 2.0

* TAPI 3.0

* Security Support Provider Interface (SSPI)

* Integrated Windows Authentication (including Kerberos and SPNEGO authentication).

* MS-CHAP v2 protocol

* Public Key Infrastructure (PKI) and Enterprise Certificate Authority support

* Terminal Services and support for the Remote Desktop Protocol (RDP)

* Internet Information Services (IIS) 5.0 and Windows Media Services 4.1

Screenshot of Windows 2000 Server:

The Server editions include more features and components, including the Microsoft Distributed File System (DFS) , Active Directory support and fault-tolerant storage.

Distributed File System:

The Distributed File System (DFS) allows shares in multiple different locations to be logically grouped under one folder, or DFS root. When users try to access a network share off the DFS root, the user is really looking at a DFS link and the DFS server transparently redirects them to the correct file server and share. A DFS root can only exist on a Windows 2000 version that is part of the server family, and only one DFS root can exist on that server.

There can be two ways of implementing a DFS namespace on Windows 2000: either through a standalone DFS root or a domain-based DFS root. Standalone DFS allows for only DFS roots on the local computer, and thus does not use Active Directory. Domain-based DFS roots exist within Active Directory and can have their information distributed to other domain controllers within the domain — this provides fault tolerance to DFS. DFS roots that exist on a domain must be hosted on a domain controller or on a domain member server. The file and root information is replicated via the Microsoft File Replication Service (FRS).

Active Directory:

A new way of organizing Windows network domains, or groups of resources, called Active Directory, is introduced with Windows 2000 to replace Windows NT's earlier domain model. Active Directory's hierarchical nature allowed administrators a built-in way to manage user and computer policies and user accounts, and to automatically deploy programs and updates with a greater degree of scalability and centralization than provided in previous Windows versions. It is one of the main reasons many corporations migrated to Windows 2000. User information stored in Active Directory also provided a convenient phone book-like function to end users. Active Directory domains can vary from small installations with a few hundred objects, to large installations with millions. Active Directory can organise and link groups of domains into a contiguous domain name space to form trees. Groups of trees outside of the same namespace can be linked together to form forests.

Active Directory services could only be installed on a Windows 2000 Server, Advanced Server, or Datacenter Server computer, and cannot be installed on a Windows 2000 Professional computer. However, Windows 2000 Professional is the first client operating system able to exploit Active Directory's new features. As part of an organization's migration, Windows NT clients continued to function until all clients were upgraded to Windows 2000 Professional, at which point the Active Directory domain could be switched to native mode and maximum functionality achieved.

Active Directory requires a DNS server that supports SRV resource records, or that an organization's existing DNS infrastructure be upgraded to support this. There must be one or more domain controllers to hold the Active Directory database and provide Active Directory directory services.

Volume fault tolerance:

Along with support for simple, spanned and striped volumes, the server family of Windows 2000 also supports fault-tolerant volume types. The types supported are mirrored volumes and RAID-5 volumes:

* Mirrored volumes: the volume contains several disks, and when data is written to one it is also written to the other disks. This means that if one disk fails, the data can be totally recovered from the other disk. Mirrored volumes are also known as RAID-1.

* RAID-5 volumes: a RAID-5 volume consists of multiple disks, and it uses block-level striping with parity data distributed across all member disks. Should a disk fail in the array, the parity blocks from the surviving disks are combined mathematically with the data blocks from the surviving disks to reconstruct the data on the failed drive "on-the-fly".

Deployment:

Windows 2000 can be deployed to a site via various methods. It can be installed onto servers via traditional media (such as CD) or via distribution folders that reside on a shared folder. Installations can be attended or unattended. During a manual installation, the administrator must specify configuration options. Unattended installations are scripted via an answer file, or a predefined script in the form of an INI file that has all the options filled in. An answer file can be created manually or using the graphical Setup manager. The Winnt.exe or Winnt32.exe program then uses that answer file to automate the installation. Unattended installations can be performed via a bootable CD, using Microsoft Systems Management Server (SMS) , via the System Preparation Tool (Sysprep), via the Winnt32.exe program using the /syspart switch or via Remote Installation Services (RIS). The ability to slipstream a service pack into the original operating system setup files is also introduced in Windows 2000. The Sysprep method is started on a standardized reference computer — though the hardware need not be similar — and it copies the required installation files from the reference computer to the target computers. The hard drive does not need to be in the target computer and may be swapped out to it at any time, with the hardware configured later. The Winnt.exe program must also be passed a /unattend switch that points to a valid answer file and a /s file that points to one or more valid installation sources.

Sysprep allows the duplication of a disk image on an existing Windows 2000 Server installation to multiple servers. This means that all applications and system configuration settings will be copied across to the new installations, and thus, the reference and target computers must have the same HALs, ACPI support, and mass storage devices — though Windows 2000 automatically detects Plug and Play devices. The primary reason for using Sysprep is to quickly deploy Windows 2000 to a site that has multiple computers with standard hardware. (If a system had different HALs, mass storage devices or ACPI support, then multiple images would need to be maintained.)

Systems Management Server can be used to upgrade multiple computers to Windows 2000. These must be running Windows NT 3.51, Windows NT 4.0, Windows 98 or Windows 95 OSR2.x along with the SMS client agent that can receive software installation operations. Using SMS allows installations over a wide area and provides centralised control over upgrades to systems.

Remote Installation Services (RIS) are a means to automatically install Windows 2000 Professional (and not Windows 2000 Server) to a local computer over a network from a central server. Images do not have to support specific hardware configurations and the security settings can be configured after the computer reboots as the service generates a new unique security ID (SID) for the machine. This is required so that local accounts are given the right identifier and do not clash with other Windows 2000 Professional computers on a network RIS requires that client computers are able to boot over the network via either a network interface card that has a Pre-Boot Execution Environment (PXE) boot ROM installed or that the client computer has a network card installed that is supported by the remote boot disk generator. The remote computer must also meet the Net PC specification. The server that RIS runs on must be Windows 2000 Server and it must be able to access a network DNS Service, a DHCP service and the Active Directory services.

Editions:

Microsoft released various editions of Windows 2000 for different markets and business needs: Professional, Server, Advanced Server and Datacenter Server. Each was packaged separately.

Windows 2000 Professional was designed as the desktop operating system for businesses and power users. It is the client version of Windows 2000. It offers greater security and stability than many of the previous Windows desktop operating systems. It supports up to two processors, and can address up to 4 GB of RAM. The system requirements are a Pentium processor of 133 MHz or greater, at least 32 MB of RAM, 650 MB of hard drive space, and a CD-ROM drive (recommended: Pentium II, 128 MB of RAM, 2 GB of hard drive space, and CD-ROM drive).

Windows 2000 Server SKUs share the same user interface with Windows 2000 Professional, but contain additional components for the computer to perform server roles and run infrastructure and application software. A significant new component introduced in the server SKUs is Active Directory, which is an enterprise-wide directory service based on LDAP. Additionally, Microsoft integrated Kerberos network authentication, replacing the often-criticised NTLM authentication system used in previous versions. This also provided a purely transitive-trust relationship between Windows 2000 domains in a forest (a collection of one or more Windows 2000 domains that share a common schema, configuration, and global catalog, being linked with two-way transitive trusts). Furthermore, Windows 2000 introduced a Domain Name Server which allows dynamic registration of IP addresses. Windows 2000 Server requires 128 MB of RAM and 1 GB hard disk space, however requirements may be higher depending on installed components

Windows 2000 Advanced Server is a variant of Windows 2000 Server operating system designed for medium-to-large businesses. It offers clustering infrastructure for high availability and scalability of applications and services, including main memory support of up to 8 gigabytes (GB) on Physical Address Extension (PAE) systems and the ability to do 8-way SMP. It supports TCP/IP load balancing and enhanced two-node server clusters based on the Microsoft Cluster Server (MSCS) in Windows NT Server 4.0 Enterprise Edition.

Limited number of copies of an IA-64 version, called Windows 2000 Advanced Server, Limited Edition were made available via OEMs. System requirements are similar to those of Windows 2000 Server however they may need to be higher to scale to larger infrastructure.

Windows 2000 Datacenter Server is a variant of Windows 2000 Server designed for large businesses that move large quantities of confidential or sensitive data frequently via a central server Like Advanced Server, it supports clustering, failover and load balancing. Its minimum system requirements are normal, but it was designed to be capable of handing advanced, fault-tolerant and scalable hardware—for instance computers with up to 32 CPUs and 64 GBs RAM, with rigorous system testing and qualification, hardware partitioning, coordinated maintenance and change control. Limited number of copies of an IA-64 version, called Windows 2000 Datacenter Server, Limited Edition were made available via OEMs. System requirements are similar to those of Windows 2000 Advanced Server however they may need to be higher to scale to larger infrastructure.

Total cost of ownership:

In October 2002, Microsoft commissioned IDC to determine the total cost of ownership (TCO) for enterprise applications on Windows 2000 versus the TCO of the same applications on Linux. IDC's report is based on telephone interviews of IT executives and managers of 104 North American companies in which they determined what they were using for a specific workload for file, print, security and networking services. IDC determined that the four areas where Windows 2000 had a better TCO than Linux — over a period of five years for an average organization of 100 employees — were file, print, network infrastructure and security infrastructure. They determined, however, that Linux had a better TCO than Windows 2000 for web serving. The report also found that the greatest cost was not in the procurement of software and hardware, but in staffing costs and downtime. While the report applied a 40% productivity factor during IT infrastructure downtime, recognizing that employees are not entirely unproductive, it did not consider the impact of downtime on the profitability of the business. The report stated that Linux servers had less unplanned downtime than Windows 2000 servers. It found that most Linux servers ran less workload per server than Windows 2000 servers and also that none of the businesses interviewed used 4-way SMP Linux computers. The report also did not take into account specific application servers — servers that need low maintenance and are provided by a specific vendor. The report did emphasize that TCO was only one factor in considering whether to use a particular IT platform, and also noted that as management and server software improved and became better packaged the overall picture shown could change.

Support lifecycle:

Windows 2000 has now been superseded by newer Microsoft operating systems: Windows 2000 Server products by Windows Server 2003 and Windows Server 2008, and Windows 2000 Professional by Windows XP Professional and Windows Vista Business.

The Windows 2000 family of operating systems moved from mainstream support to the extended support phase on 30 June 2005. Microsoft says that this marks the progression of Windows 2000 through the Windows lifecycle policy. Under mainstream support, Microsoft freely provides design changes if any, service packs and non-security related updates in addition to security updates, whereas in extended support, service packs are not provided and non-security updates require contacting the support personnel by e-mail or phone. Under the extended support phase, Microsoft continues to provide critical security updates every month for all components of Windows 2000 (including Internet Explorer 5.0 SP4) and paid per-incident support for technical issues. Because of Windows 2000's age, Microsoft is not offering current components such as Internet Explorer 7 for it. They claim that IE 7 relies on security features designed only for Windows XP Service Pack 2 and Windows Vista, and thus porting to the Windows 2000 platform would be non-trivial. Microsoft is strongly advising all users still running Windows 2000 Professional and Server to consider upgrading to current operating systems for increased security. While users of Windows 2000 are eligible to receive the upgrade license for Windows Vista or Windows Server 2008, neither of these operating systems can directly perform an upgrade installation from Windows 2000; a clean installation must be performed on computers running Windows 2000.

All Windows 2000 support including security updates and security-related hotfixes will be terminated on 13 July 2010.

Windows 2000 has received four full service packs and one rollup update package following SP4, which is the last service pack. These were: SP1 on 15 August 2000, SP2 on 16 May 2001, SP3 on 29 August 2002 and SP4 on 26 June 2003. Microsoft phased out all development of its Java Virtual Machine (JVM) from Windows 2000 in SP3. Internet Explorer 5.01 has also been upgraded to the corresponding service pack level.

Many Windows 2000 users were hoping for a fifth service pack, but Microsoft cancelled this project early in its development, and instead released Update Rollup 1 for SP4, a collection of all the security-related hotfixes and some other significant issues. The Update Rollup, however, does not include all non-security related hotfixes and is not subjected to the same extensive regression testing as a full service pack. Microsoft states that this update will meet customers' needs better than a whole new service pack, and will still help Windows 2000 customers secure their PCs, reduce support costs, and support existing computer hardware.

Although Windows 2000 is the last NT-based version of Microsoft Windows which does not include Windows Product Activation, Microsoft has introduced Windows Genuine Advantage for certain downloads and non-critical updates from the Download Center for Windows 2000.

Security criticisms:

A number of potential security issues have been noted in Windows 2000. A common complaint is that "by default, Windows 2000 installations contain numerous potential security problems. Many unneeded services are installed and enabled, and there is no active local security policy". In addition to insecure defaults, according to the SANS Institute, the most common flaws discovered are remotely exploitable buffer overflow vulnerabilities. Other criticized flaws include the use of vulnerable encryption techniques.

Computer worms first became publicized when Windows 2000 was the dominant server operating system Code Red and Code Red II were famous (and much discussed) worms that exploited vulnerabilities of the Windows Indexing Service of Windows 2000's Internet Information Services (IIS) In August 2003, two major worms called Sobig and Blaster began to attack millions of Microsoft Windows computers, resulting in the largest downtime and clean-up cost to that date The 2005 Zotob worm was blamed for security compromises on Windows 2000 machines at the U.S. Department of Homeland Security, the New York Times Company, ABC and CNN.

References:

http://en.wikipedia.org

Windows 98 SE

2010-08-14T01:20:00.000-07:00

Windows 98 SE

Windows 98 (codenamed Memphis) is a graphical operating system released on 25 June 1998 by Microsoft and the successor to Windows 95. Like its predecessor, it is a hybrid 16-bit/32-bit monolithic product based on MS-DOS. Windows 98 was succeeded by Windows Me on 14 September 2000.

Windows 98 Second Edition:
Windows 98 Second Edition (often shortened to SE) is an updated release of Windows 98, released on 5 May 1999. It includes fixes for many minor issues, improved USB support, and the replacement of Internet Explorer 4.0 with the significantly faster and less error-prone Internet Explorer 5.0. Also included is Internet Connection Sharing, which allows multiple computers on a LAN to share a single Internet connection through Network Address Translation. Other features in the update include Microsoft NetMeeting 3.0 and integrated support for DVD-ROM drives. A memory overflow issue was resolved which in the older version of Windows 98 would crash most systems if left running for 49.7 days.Also included on the CD-ROM is the option to install Microsoft Plus! themes for Windows 98. Windows 98SE could be obtained as retail upgrade and full version packages, as well as OEM and a Second Edition Updates Disc for existing Windows 98 users.

New driver standards:
Windows 98 was the first operating system to use the Windows Driver Model (WDM). This fact was not well published when Windows 98 was released and most hardware producers continued to develop drivers for the older driver standard, VxD. The WDM standard spread years after its release, mostly through Windows 2000 and Windows XP, because these systems are not compatible with the older VxD standard. Today, even if hardware producers are not developing drivers optimized for Windows 98, the drivers written to WDM standards are compatible with Windows 98 based systems.

System requirements:
* 486DX-2/66 MHz or higher processor (Pentium processor recommended)
* 16 MB of RAM (24 MB recommended, it's possible to run on 8 MB machines with /im option used during the installation process)
* At least 500 MB of space available on HDD. The amount of space required depends on the installation method and the components selected, but virtual memory and system utilities as well as drivers should be taken into consideration.
* Upgrading from Windows 95 (FAT16) or 3.1 (FAT): 140-400 MB (typically 205 MB).
* New installation (FAT32): 190-305 MB (typically 210 MB).
* Note: Both Windows 98 and Windows 98 SE can have significant problems associated with hard drives that are over 32 Gigabytes (GB) in size. This issue only occurs with certain Phoenix BIOS settings. A software update has been made available to fix this shortcoming.
* Note2: Also, both Windows 98 and Windows 98 SE are unable to handle hard drives that are over 137 Gigabytes (GB) in size, because of missing 48 Bit LBA support. Data corruption is possible. An experimental third party software update is available to fix this shortcoming
* VGA or higher resolution monitor
* CD-ROM or DVD-ROM drive (The First Edition was also released on Floppy Disks, but is very rare)
* Microsoft Mouse or compatible pointing device (optional).
Like its predecessor, Windows 95, and its successor, Windows Millennium Edition (Me), users can bypass hardware requirement checks with the undocumented /im setup switch. This allows installation on computers with processors as old as the 80386.

Press demonstration:
The release of Windows 98 was preceded by a notable press demonstration at Comdex in April 1998. Microsoft CEO Bill Gates was highlighting the operating system's ease of use and enhanced support for Plug and Play (PnP). However, when presentation assistant Chris Capossela plugged a scanner in and attempted to install it, the operating system crashed, displaying a Blue Screen of Death. Gates remarked after applause and cheering from the audience, "That must be why we're not shipping Windows 98 yet." Video footage of this event became a popular Internet phenomenon.

Windows 98 System tools:
* ScanDisk - System utility used to maintain the file system. It offers a DOS and a GUI version. Used to check the integrity of the file system and files stored within.
* Disk Defragmenter - Used to counter the negative effects of filesystem fragmentation. It collects fragmented file parts, reconnects them and rearranges all files in optimal order, thus speeding up file access and allowing faster boot times.
* Scanreg - Used to restore the System registry. It tests the registry's integrity and saves a backup copy each time. The maximum amount of copies could be customized by the user through "scanreg.ini" file. Due to a bug the oldest registry copy available cannot be restored (before restoration, the current configuration is backed up and it erases the oldest registry backup listed). The restoration of a faulty registry can only be done in DOS mode. Important DOS commands: scanreg/opt - optimizes the registry by deleting dead entries; scanreg/fix - repairs registry settings.
* Msconfig - A system utility used to disable programs and services which are not required to run the computer. It is a very efficient tool that can multiply the system's stability and speed.
* Regedit - Allows manual editing of the registry.

Modernizing and Expanding:
All versions of DirectX up to 9.0c can be installed on Windows 98 SE. Microsoft .NET Framework up to version 2.0 is supported. Internet Explorer can be updated to version 6.0 (6.00.2800.1106 Service Pack 1), the same version included with Windows XP SP1 (and the last version available for versions of Windows prior to XP), but it cannot receive current Internet Explorer security updates. Windows 98 can handle the Visual C++ 2005 library and L2TP/IPSec VPN client by Microsoft as well as versions of the Microsoft Installer (MSIA) services up to 2.0. Windows Media Player 9.0 is also supported and can be installed without problems. Due to incompatibilities with the Cairo interface used in version 1.9 of the Gecko Layout Engine, versions of Mozilla Firefox, starting with the 3.0 release, will no longer support Windows 98 or Windows Me, but all versions of the Opera web browser up to and including the latest 9.64 release continue to function. There is also a project to provide a compatibility layer which allows the functioning of software requiring Windows 2000 and above. Support for more than 512 MB RAM is achieved with a third-party patch or by modifying system.ini. Support for hard disks above 137 GB and up to 2 TB is also possible via several third-party tools.

Product life cycle:
Microsoft planned to discontinue its support for Windows 98 on 16 January 2004. However, due to the continued popularity of the operating system (27% of Google's pageviews were on Windows 98 systems during October-November, 2003) Microsoft decided to maintain support until 11 July 2006. Support for Windows Me also ended on this date. By that time, Windows 98 market share had diminished to 2.7%.

Dropped features:
There was a feature planned for Windows 98, dubbed DeskBar, that was removed soon before retail release, likely due to time constraints. However, the developers left a way to find the tab for settings to do with this feature, which can be unhidden by holding "Control" when selecting Properties on the taskbar context menu.

References:
http://en.wikipedia.org

Windows 98

2010-08-14T01:17:00.000-07:00

Windows 98

Windows 98 Second Edition:

Windows 98 Second Edition (often shortened to SE) is an updated release of Windows 98, released on 5 May 1999. It includes fixes for many minor issues, improved USB support, and the replacement of Internet Explorer 4.0 with the significantly faster and less error-prone Internet Explorer 5.0. Also included is Internet Connection Sharing, which allows multiple computers on a LAN to share a single Internet connection through Network Address Translation. Other features in the update include Microsoft NetMeeting 3.0 and integrated support for DVD-ROM drives. A memory overflow issue was resolved which in the older version of Windows 98 would crash most systems if left running for 49.7 days.Also included on the CD-ROM is the option to install Microsoft Plus! themes for Windows 98.Windows 98SE could be obtained as retail upgrade and full version packages, as well as OEM and a Second Edition Updates Disc for existing Windows 98 users.

New driver standards:

Windows 98 was the first operating system to use the Windows Driver Model (WDM). This fact was not well published when Windows 98 was released and most hardware producers continued to develop drivers for the older driver standard, VxD. The WDM standard spread years after its release, mostly through Windows 2000 and Windows XP, because these systems are not compatible with the older VxD standard. Today, even if hardware producers are not developing drivers optimized for Windows 98, the drivers written to WDM standards are compatible with Windows 98 based systems.

System requirements:

* 486DX-2/66 MHz or higher processor (Pentium processor recommended)

* 16 MB of RAM (24 MB recommended, it's possible to run on 8 MB machines with /im option used during the installation process)

* At least 500 MB of space available on HDD. The amount of space required depends on the installation method and the components selected, but virtual memory and system utilities as well as drivers should be taken into consideration.

* Upgrading from Windows 95 (FAT16) or 3.1 (FAT): 140-400 MB (typically 205 MB).

* New installation (FAT32): 190-305 MB (typically 210 MB).

* Note: Both Windows 98 and Windows 98 SE can have significant problems associated with hard drives that are over 32 Gigabytes (GB) in size. This issue only occurs with certain Phoenix BIOS settings. A software update has been made available to fix this shortcoming.[4]

* Note2: Also, both Windows 98 and Windows 98 SE are unable to handle hard drives that are over 137 Gigabytes (GB) in size, because of missing 48 Bit LBA support. Data corruption is possible. An experimental third party software update is available to fix this shortcoming.[5]

* VGA or higher resolution monitor

* CD-ROM or DVD-ROM drive (The First Edition was also released on Floppy Disks, but is very rare)

* Microsoft Mouse or compatible pointing device (optional).

Like its predecessor, Windows 95, and its successor, Windows Millennium Edition (Me), users can bypass hardware requirement checks with the undocumented /im setup switch. This allows installation on computers with processors as old as the 80386.

Press demonstration:

The release of Windows 98 was preceded by a notable press demonstration at Comdex in April 1998. Microsoft CEO Bill Gates was highlighting the operating system's ease of use and enhanced support for Plug and Play (PnP). However, when presentation assistant Chris Capossela plugged a scanner in and attempted to install it, the operating system crashed, displaying a Blue Screen of Death.Gates remarked after applause and cheering from the audience, "That must be why we're not shipping Windows 98 yet." Video footage of this event became a popular Internet phenomenon.

Windows 98 System tools:

* ScanDisk - System utility used to maintain the file system. It offers a DOS and a GUI version. Used to check the integrity of the file system and files stored within.

* Disk Defragmenter - Used to counter the negative effects of filesystem fragmentation. It collects fragmented file parts, reconnects them and rearranges all files in optimal order, thus speeding up file access and allowing faster boot times.

* Scanreg - Used to restore the System registry. It tests the registry's integrity and saves a backup copy each time. The maximum amount of copies could be customized by the user through "scanreg.ini" file. Due to a bug the oldest registry copy available cannot be restored (before restoration, the current configuration is backed up and it erases the oldest registry backup listed). The restoration of a faulty registry can only be done in DOS mode. Important DOS commands: scanreg/opt - optimizes the registry by deleting dead entries; scanreg/fix - repairs registry settings.

* Msconfig - A system utility used to disable programs and services which are not required to run the computer. It is a very efficient tool that can multiply the system's stability and speed.

* Regedit - Allows manual editing of the registry.

Modernizing and Expanding:

All versions of DirectX up to 9.0c can be installed on Windows 98 SE. Microsoft .NET Framework up to version 2.0 is supported. Internet Explorer can be updated to version 6.0 (6.00.2800.1106 Service Pack 1), the same version included with Windows XP SP1 (and the last version available for versions of Windows prior to XP), but it cannot receive current Internet Explorer security updates. Windows 98 can handle the Visual C++ 2005 library and L2TP/IPSec VPN client by Microsoft as well as versions of the Microsoft Installer (MSIA) services up to 2.0. Windows Media Player 9.0 is also supported and can be installed without problems. Due to incompatibilities with the Cairo interface used in version 1.9 of the Gecko Layout Engine, versions of Mozilla Firefox, starting with the 3.0 release, will no longer support Windows 98 or Windows Me but all versions of the Opera web browser up to and including the latest 9.64 release continue to function. There is also a project to provide a compatibility layer which allows the functioning of software requiring Windows 2000 and above. Support for more than 512 MB RAM is achieved with a third-party patch or by modifying system.ini. Support for hard disks above 137 GB and up to 2 TB is also possible via several third-party tools.

Product life cycle:

Microsoft planned to discontinue its support for Windows 98 on 16 January 2004. However, due to the continued popularity of the operating system (27% of Google's pageviews were on Windows 98 systems during October-November, 2003), Microsoft decided to maintain support until 11 July 2006. Support for Windows Me also ended on this date. By that time, Windows 98 market share had diminished to 2.7%.

Dropped features:

There was a feature planned for Windows 98, dubbed DeskBar, that was removed soon before retail release, likely due to time constraints. However, the developers left a way to find the tab for settings to do with this feature, which can be unhidden by holding "Control" when selecting Properties on the taskbar context menu.

References:

http://en.wikipedia.org

Windows NT 4.0

2010-08-14T01:14:00.000-07:00

Windows NT 4.0

Windows NT 4.0 is a preemptive, graphical and business-oriented operating system designed to work with either uniprocessor or symmetric multi-processor computers. It is a release of Microsoft's Windows NT line of operating systems and was released to manufacturing on 29 July 1996 (public release on 24 Aug 1996). It is a 32-bit Windows system available in both workstation and server editions with a graphical environment similar to that of Windows 95. The "NT" designation in the product's title initially stood for "New Technology" according to Microsoft's then-CEO Bill Gates, but now no longer has any specific meaning. Windows NT 4.0 was succeeded by Windows 2000 in February 2000. Windows NT 4.0 is classified as a hybrid kernel operating system.

Overview:

While providing much greater stability than Windows 95, it was also less flexible from a desktop perspective. Much of the stability is gained by the use of protected memory and the hardware abstraction layer. Direct hardware access was disallowed and “misbehaving” applications were terminated without needing the computer to be restarted. The trade-off was that NT required an excessive amount of memory in comparison to consumer targeted products such as Windows 95.

While nearly all programs written for Windows 95 will run on Windows NT, the majority of 3D games will not, due in part to NT 4.0 having limited support for DirectX. Third party device drivers were in fact allowed to access the hardware directly and poorly written drivers were a frequent source of “stop errors”. Such failures became to be referred to as the “blue screen of death" or BSOD and would require the system to be restarted in such cases. These errors were rare and it was not uncommon for NT servers or workstations to run for months at a time without failure. By comparison Windows consumer versions at the time were much less stable and popularized the belief that all Windows versions were unreliable.

Windows NT 4.0 is also less user-friendly than Windows 95 when it comes to certain maintenance and management tasks; there is, for instance, no support by default for “Plug-and-play” (although limited support could be installed later) which greatly simplifies installation of hardware devices or support for USB devices. Many basic DOS applications would run however graphical DOS applications would not run due to the way they accessed graphics hardware.

The difference between the NT and "9x" lines of Windows ended with the arrival of Windows XP, by which time the gaming APIs—such as OpenGL and DirectX—had matured sufficiently to be more efficient to write for than common PC hardware and the hardware itself had become powerful enough to handle the API processing overhead acceptably.

Windows NT 4.0 is the last major release of of Microsoft Windows to support the Alpha, MIPS or PowerPC CPU architectures. It remained in use by businesses for a number of years, despite Microsoft's many efforts to get customers to upgrade to Windows 2000 and newer versions. It was also the last release in the Windows NT line to use the "Windows NT" name.

Features:

The most noticeable difference from Windows NT 3.51 is that Windows NT 4.0 has the user interface of Windows 95, including the Windows Shell, Windows Explorer (known as Windows NT Explorer), and the use of "My" nomenclature (e.g. My Computer). It also includes most applications introduced with Windows 95.

The server editions of Windows NT 4.0 include a built-in web server, Internet Information Services version 2.0. It also natively supported plugins and extensions of Microsoft FrontPage, a web site creation and management application.

Other important features included with this release were Microsoft Transaction Server for network applications, and Microsoft Message Queuing (MSMQ), which improved communication.

One significant difference from previous versions of Windows NT is that the Graphics Device Interface (GDI) is incorporated into the kernel to speed up the graphical user interface (GUI), resulting in a significant performance improvement over Windows NT 3.51 and also creating the requirement to have graphics drivers located in the kernel, resulting in potential stability issues.

Windows NT 4.0 also included a new Windows Task Manager application. Previous versions of Windows NT included the Task List application, but it only shows applications currently in memory. To monitor how much CPU and memory resources are being used, users were forced to use Performance Monitor. The task manager offers a more convenient way of getting a snapshot of all the applications running on the system at any given time.

Unlike Windows 95, Windows NT 4.0 does not support Direct3D and USB. Windows 2000 introduced native USB and Direct3D support to Windows NT. Third party utilities also exist that provide DirectX support in Windows NT 4.0.

Microsoft offered up to Internet Explorer 6.0 SP1 for NT 4.0, provided it was updated to handle it.

Editions:

Windows NT 4.0 Server was included in versions 4.0 and 4.5 of BackOffice Small Business Server suite.

Servers:

* Windows NT 4.0 Server, released in 1996, was designed for small-scale business server systems.

* Windows NT 4.0 Server, Enterprise Edition, released in 1997, is the precursor to the Enterprise line of the Windows server family. Enterprise Server was designed for high-demand, high-traffic networks.

* Windows NT 4.0 Terminal Server, released in 1998, allows the users to log on remotely. The same functionality was called Terminal Services in Windows 2000 and later server releases, and also powers the Remote Desktop feature that first appeared in Windows XP.

Client:

Windows NT 4.0 Workstation was designed for use as the general business desktop operating system.

Embedded:

Windows NT 4.0 Embedded (abbreviated NTe) is an edition of Windows NT 4.0 that was aimed at computer-powered appliances, vending machines, ATMs and other devices that cannot be considered computers per se. It is the same system as the standard Windows NT 4.0, but it comes packaged in a database of components and dependencies, from which a developer can choose individual components to build customized setup CDs and hard disk boot images. It was succeeded by Windows XP Embedded.

Option Pack:

An 'Option Pack' is available as a free-bundled CD around 1998, which includes IIS 4.0, MTS, MSMQ and a pack of new software.

Service Packs:

Microsoft released Windows NT 4.0 service packs primarily to fix bugs. Windows NT 4.0, during the product's lifecycle, had several service packs, as well as numerous service rollup packages and option packs. The last full service pack was Service Pack 6a (SP6a).

A SP7 was planned at one stage in early 2001, but this became the Post SP6a Security Rollup and not a full Service Pack, released 16 months after Windows 2000 and nearly three months prior to Windows XP

The service packs and an option pack were also released to add features. These included newer versions of Internet Information Services, versions 3.0, and 4.0, support for Active Server Pages, public-key and certificate authority functionality, smart card support, improved symmetric multiprocessing (SMP) scalability, clustering capabilities, and component object model (COM) support, among others

Security:

On 7 January 2005, Microsoft stopped providing security updates for Windows NT 4.0, due to major security flaws including MS03-010, which according to Microsoft could not be patched without significant changes to the core operating system. According to the security bulletin, "Due to [the] fundamental differences between Windows NT 4.0 and Windows 2000 and its successors, it is infeasible to rebuild the software for Windows NT 4.0 to eliminate the vulnerability. To do so would require rearchitecting a very significant amount of the Windows NT 4.0 operating system, and there would be no assurance that applications designed to run on Windows NT 4.0 would continue to operate on the patched system."

Between June 2003 and June 2007, 127 security flaws were identified and patched in Windows 2000 Server, many of which may also affect Windows NT 4.0; however, Microsoft doesn't test security bulletins against unsupported software. Because of this, Microsoft is recommending current Windows NT customers to upgrade to a supported operating system such as Windows Server 2003, or Windows Server 2008.

Legacy:

The stability of Windows NT offered reduced support costs over Windows 95 or Windows 98. It was later supplanted by Windows 2000 which was based on NT and largely bridged the gap between NT and consumer Windows versions. Windows XP, Windows Vista and subsequent server versions were later released which completed the unification of the core architecture of all Windows versions which evolved directly from Windows NT.

References:

http://en.wikipedia.org

Windows 95

2010-08-14T01:09:00.000-07:00

Windows 95

Windows 95 is a consumer-oriented graphical user interface-based operating system. It was released on August 24, 1995 by Microsoft,[2] and was a significant progression from the company's previous Windows products. During development it was referred to as Windows 4.0 or by the internal codename Windows Chicago.

Windows 95 was intended to integrate Microsoft's formerly separate MS-DOS and Windows products and includes an enhanced version of DOS, often referred to as MS-DOS 7.0. It features significant improvements over its predecessor, Windows 3.1, most visibly in the graphical user interface (GUI). There were also major changes made at lower levels of the operating system.

In the marketplace, Windows 95 was a major success, and within a year or two of its release had become the most successful operating system ever produced. It also had the effect of driving other major players in the DOS-compatible operating system out of business, something which would later be used in court against Microsoft. Some three years after introduction, Windows 95 was succeeded by Windows 98.

User interface:

The basic elements of the interface introduced in Windows 95 -- including the taskbar, Start button and menu, and the Windows Explorer file manager -- remain fundamentally unchanged in later versions of Windows, such as Windows Server 2008 and Windows 7, more than a decade later. The word "Start" was dropped from the button in Windows Vista in 2006, with the company preferring to label the button with the Windows logo ("Start" is still present as a tooltip and in the classic GUI mode).

When released for Windows 95, Internet Explorer 4.0 came with an optional shell update known as Windows Desktop Update that changed the user interface significantly. That update gave Windows 95 (and Windows NT 4.0) features that would become the graphical user interface of Windows 98.

Technical improvements:

Windows 95 included support for 255-character mixed-case long filenames and preemptively multitasked pseudo-protected-mode 32-bit applications. Whereas earlier versions of Windows are optional "DOS extending shells" requiring an MS-DOS or MS-DOS compatible operating system (usually sold separately). Windows 95 incorporated MS-DOS into a consolidated operating system, which was a significant marketing change. The release of Windows 95 also marked wider acceptance of Plug and Play standards on the IBM PC platform.

Long file names:

32-bit File Access is necessary for the long file names feature introduced with Windows 95 through the use of the VFAT file system. It is available to both Windows programs and MS-DOS programs started from Windows (they have to be adapted slightly, since accessing long file names requires using larger pathname buffers and hence different system calls). Competing DOS-compatible operating systems released before Windows 95 cannot see these names. Using older versions of DOS utilities to manipulate files means that the long names are not visible and are lost if files are moved or renamed, as well as by the copy (but not the original), if the file is copied. During a Windows 95 automatic upgrade of an older Windows 3.1 system, DOS and third-party disk utilities which can destroy long file names are identified and made unavailable (Microsoft Anti-Virus for Windows indicated that the upgrade program was itself a computer virus). When Windows 95 is started in DOS mode, e.g. for running DOS programs, low-level access to disks is locked out. In case the need arises to depend on disk utilities that do not recognize long file names, such as MS-DOS 6.x's defrag utility, a program called LFNBACK for backup and restoration of long file names is provided on the CD-ROM. The program is in the \ADMIN\APPTOOLS\LFNBACK directory of the Windows 95 CD-ROM.

32-bit:

Windows 95 followed Windows for Workgroups 3.11 with its lack of support for older, 16-bit x86 processors, thus requiring an Intel 80386 (or compatible).

The introduction of 32-bit File Access in Windows for Workgroups 3.11 meant that 16-bit real mode MS-DOS is not used for managing the files while Windows is running, and the earlier introduction of the 32-bit Disk Access means that the PC BIOS is not used for managing hard disks. This essentially reduces MS-DOS to the role of a boot loader for the protected-mode Windows kernel. DOS can be used for running old-style drivers for compatibility, but Microsoft discourages using them, as this prevents proper multitasking and impairs system stability. Control Panel allows a user to see what MS-DOS components are used by the system; optimal performance is achieved when they are all bypassed. The Windows kernel uses MS-DOS style real-mode drivers in Safe Mode, which exists to allow a user to fix problems relating to loading native, protected-mode drivers.

Release:

Beta:

Several Windows 95 betas were released before the final launch.

Build 58 introduced a Start menu prototype. It divided the functions of the Windows 95 Start menu up into three buttons. Future Chicago builds combined these three into the Start button still recognized today.

Build 58 included a new File Manager, Chicago Explorer, which remained relatively unchanged in the initial version of Windows 95 and in Windows NT 4.0. Build 58 still included Program Manager as found in Windows 3.1, although this application was supplemented by the new desktop and taskbar/Start menu designs.

This build also introduced shortcuts (Chicago referred to them as Links) and native right click functionality, which Windows 3.1 lacked. It also introduced long file name support.

Prior to the official release, the American public was given a chance to preview Windows 95 in the Windows 95 Preview Program. For US$19.95, users were sent a set of 3½" floppy diskettes that would install Windows 95 either as an upgrade to Windows 3.1x or as a fresh install on a clean computer. Users who bought into the program were also given a free preview of The Microsoft Network (MSN), the online service that Microsoft launched with Windows 95. The preview versions expired in November 1995, after which the user would have to purchase their own copy of the final version of Windows 95.

Final:

Windows 95 was released with great fanfare, including a commercial featuring the Rolling Stones song "Start Me Up" (a reference to the Start button) It was widely reported that Microsoft paid the Rolling Stones between US$8 and US$14 million for the use of the song (from the 1981 album Tattoo You) in the '95 advertising campaign. According to sources at Microsoft, however, this was just a rumor spread by the Stones to increase their market value, and Microsoft actually paid a fraction of that amount A 30 minute promotional video, labeled a "cyber sitcom", featuring Jennifer Aniston and Matthew Perry, was also released to showcase the features of Windows 95. Microsoft's US$300 million dollar advertising campaign featured stories of people waiting in line outside stores to get a copy.

In the UK, the largest computer chain PC World received a large number of oversized Windows 95 boxes, posters and point of sale material, and many branches opened at midnight to sell the first copies of the product, although these customers were far fewer in number than publicity had suggested.

In the United States, the Empire State Building in New York City was lit to match the colors of the Windows logo. In Canada, a 300-foot banner was hung from the top of the CN Tower in Toronto. Copies of The Times were available for free in the United Kingdom where Microsoft paid for 1.5 million issues (twice the daily circulation at the time).

The release included a number of "Fun Stuff" items on the CD, including music videos from Edie Brickell and Weezer.

Internet Explorer:

Windows 95 originally shipped without Internet Explorer, and the default network installation did not install TCP/IP, the network protocol used on the Internet. At the release date of Windows 95, Internet Explorer 1.0 was available, but only in the Plus! add-on pack for Windows 95, which was a separate product. The Plus! Pack did not reach as many retail consumers as the operating system itself (it was mainly advertised for its add-ons such as themes and better disk compression) but was usually included in pre-installed (OEM) sales, and at the time of Windows 95 release, the web was being browsed mainly with a variety of early web browsers such as Netscape (promoted by products such as Internet in a Box).

Windows 95 OEM Service Release 1 was the first release of Windows to include Internet Explorer (Codenamed O'Hare) with the OS, including version 2.0. While there was no uninstaller, it could be deleted easily if the user so desired. The included version switched to Internet Explorer 3 when it came out. The installation of Internet Explorer 4 on Windows 95 (or the OSR2.5 version preinstalled on a computer) gave Windows 95 active desktop and browser integration into Windows Explorer, known as the Windows Desktop Update. The CD version of the last release of Windows 95, OEM Service Release 2.5 (Version 4.00.950C), includes Internet Explorer 4, and installs it after Windows 95's initial setup and first boot is complete.

Only the 4.x series of the browser contained the Windows Desktop Update features, so anyone wanting the new shell had to install IE4 with the desktop update before installing a newer version of Internet Explorer. The last version of Internet Explorer supported on Windows 95 is Internet Explorer 5.5 which was released in 2000. Windows 95 shipped with Microsoft's own dial-up online service called The Microsoft Network.

Editions:

While Windows 95 was originally sold as a shrink-wrapped product, later editions were provided only to computer OEMs for installation on new PCs. The term OEM Service Release is frequently abbreviated OSR, as in OSR1 or OSR2.1. Thus, for example, OSR1 was the OEM release that was identical to Windows 95 retail with Service Pack 1 applied (with the addition of Internet Explorer). In order to maintain compatibility with existing programs, Windows 95 has an internal version number of "4.00.950", regardless of the internal build number, thus reflecting Windows 95's alternative identity as "Windows 4.0" (similarly, the original edition of Windows 98 has an internal version number of Windows 4.10.1998.) Later versions are sometimes referred to by the trailing letter appended to this version string, such as Windows 95 B for OSR2 and OSR2.1.

Windows 95 partially supports USB as of OSR 2.1, though it is disabled by default and is limited by driver availability.

System requirements:

Official system requirements were an Intel 80386 DX CPU of any speed, 4 MB of system RAM, and 50 MB of hard drive space. These minimal claims were made in order to maximize the available market of Windows 3.1 converts. This configuration was distinctly suboptimal for any productive use on anything but single tasking dedicated workstations due to the heavy reliance on virtual memory. Also, in some cases, if any networking or similar components were installed the system would refuse to boot with 4 megabytes of RAM. It was possible to run Windows 95 on a 386 SX but this led to even less acceptable performance due to its 16-bit external data bus. To achieve optimal performance, Microsoft recommends an Intel 80486 or compatible microprocessor with at least 8 MB of RAM

Windows 95 was superseded by Windows 98 and could still be directly upgraded by both Windows 2000 and Windows Me. On 31 December 2001, Microsoft ended its support for Windows 95, making it an "obsolete" product according to the Microsoft Lifecycle Policy Even though support for Windows 95 has ended, the software still remains in use on some home and school computers because of budget issues, a lack of knowledge or lack of desire to upgrade to newer editions of Windows. In addition, some video game enthusiasts choose to use Windows 95 for their legacy system to play old DOS games, although some other versions of Windows such as Windows 98 can also be used for this purpose.

Windows 95 has been released on both floppy disks and on CD-ROM, as some computer systems at the time did not include a CD-ROM drive. The retail floppy disk version of Windows 95 came on 13 DMF formatted floppy disks, while OSR 2.1 doubled the floppy count to 26. Both versions exclude additional software that CD-ROM might have featured. Microsoft Plus! for Windows 95 was also available on floppy disks.

References:

http://en.wikipedia.org

Windows NT 3.51

2010-08-14T01:05:00.000-07:00

Windows NT 3.51

Windows NT 3.51 is the third release of Microsoft's Windows NT line of operating systems. It was released on May 30, 1995, nine months after Windows NT 3.5. The release provided two notable feature improvements; firstly NT 3.51 was the first of a short-lived outing of Microsoft Windows on the PowerPC CPU architecture. The second most significant enhancement offered through the release was that it provides client/server support for interoperating with Windows 95, which was released three months after NT 3.51. Windows NT 4.0 became its successor a year later; Microsoft continued to support 3.51 until December 31, 2001.

Overview:

The release of Windows NT 3.51 was dubbed "the PowerPC release" at Microsoft. The original intention was to release a PowerPC edition of NT 3.5, but according to Microsoft's David Thompson, "we basically sat around for 9 months fixing bugs while we waited for IBM to finish the Power PC hardware Editions of NT 3.51 were also released for Intel's x86, MIPS, and DEC Alpha architectures.

Despite the significant difference in the kernel base, Windows NT 3.51 is readily able to run a large number of Win32 applications designed for Windows 95. Most recent 32-bit applications will not work as the developers have prevented their application from working with any Windows version earlier than Windows 98, also because some applications do not work properly with the older Windows NT 3.51 interface. Despite this, Microsoft in their application releases muddied the issue, releasing 32-bit versions of Microsoft Office right up to Office 97 SR2b, but relying upon 16-bit versions of Internet Explorer technology. This is probably because 32-bit versions of Internet Explorer 4.0 and later integrated with the Windows 95 desktop, and NT 3.51 still used the Windows 3.1 desktop. Later on, up to IE 5.0, but not later 5.x versions, were offered.

Microsoft also released test versions of a shell refresh, named the Shell Technology Preview. The update was designed to replace the Windows 3.x Program Manager/File Manager based shell with a Windows Explorer-based graphical user interface. The release provided capabilities quite similar to that of the Windows "Chicago" (codename for Windows 95) shell during its late beta phases, however was intended to be nothing more than a test release There were two public releases of the Shell Technology Preview, made available to MSDN and CompuServe users; May 26, 1995 and August 8, 1995. Both held Windows Explorer builds of 3.51.1053.1. The Shell Technology Preview program never saw a final release under NT 3.51. The entire program was moved across to the Cairo development group who finally integrated the new shell design into the NT code with the release of NT 4.0 in July 1996.

Five Service Packs were released for NT 3.51, which introduced both bug fixes and new features. Service Pack 5, for example, fixed issues related to the Year 2000 problem.

NT 3.51 was the last of the series to run on a Intel 80386 processor. This, its ability to use HPFS partitions (which Windows 2000 and later could not) , and its ability to run at least some of the common control API, means that it still finds a place for occasional use on older machines.

Hardware requirements:

Windows NT 3.51 hardware requirements:

"Windows NT Workstation"

Processor: 386 or 486/25 processor

Memory: 12 MB RAM

Video: VGA video

Hard disk drive free space: 90 MB

"Windows NT Server"

Processor: 386 or 486/25 processor

Memory: 16 MB RAM

Video: VGA video

Hard disk drive free space: 90 MB

Windows NT 3.51 supports IDE, EIDE, SCSI and ESDI hard drives. The only EIDE addressing schemes supported are Logical block addressing, ONTrack Disk Manager, EZDrive, and Extended cylinder-head-sector.

References:

http://en.wikipedia.org

Windows NT 3.5

2010-04-10T04:12:00.000-07:00

Windows NT 3.5

Windows NT 3.5 is the second release of the Microsoft Windows NT operating system. It was released on September 21, 1994.

One of the primary goals during Windows NT 3.5's development was to increase the speed of the operating system; as a result, the project was given the codename "Daytona" in reference to the Daytona International Speedway in Daytona Beach, Florida

Overview:

This is the first Windows NT to adopt the names Windows NT Workstation and Windows NT Server for its editions. The editions of the previous Windows NT release, Windows NT 3.1, were named Windows NT and Windows NT Advanced Server.

New features in Windows NT 3.5 include the new startup screen. The interface was updated to be consistent with the Windows for Workgroups 3.xx. It also upgraded Object Linking and Embedding (OLE) support from version 1.0 to version 2.0 and is more efficient - performance is higher and it requires less memory than Windows NT 3.1.

In July 1995, Windows NT 3.5 with Service Pack 3 was rated by the National Security Agency as complying with TCSEC C2 criteria.

Windows NT 3.5 refuses to install on a processor newer than the original Pentium (P5 core).

Windows NT 3.51 fixed this. It is however possible to modify files on the install CD which will allow it to install.

Editions:

* Windows NT Server

* Windows NT Workstation

References:

http://en.wikipedia.org

Windows NT 3.1

2010-03-13T13:53:00.000-08:00

Windows NT 3.1

Windows NT 3.1 is the first release of Microsoft's Windows NT line of server and business desktop operating systems, and was released to manufacturing on 27 July 1993. The version number was chosen to match the one of Windows 3.1, the then-latest operating environment from Microsoft, on account of the similar visual appearance of the user interface. Two editions of NT 3.1 were made available, Windows NT 3.1 and Windows NT Advanced Server. It was succeeded by Windows NT 3.5 in September 1994.

It could run on Intel x86, DEC Alpha, and MIPS R4000 CPUs.

Development:

{{seealso|History of Microsoft Windows Development of Windows NT started in November 1988, after Microsoft hired a group of developers from Digital Equipment Corporation led by Dave Cutler. Many elements of the design reflect earlier DEC experience with VMS and RSX-11. The operating system was designed to run on multiple instruction set architectures and multiple hardware platforms within each architecture. The platform dependencies are largely hidden from the rest of the system by a kernel mode module called the HAL.

Windows NT was originally intended to be OS/2 3.0, the third version of the operating system developed jointly by Microsoft and IBM. When Windows 3.0 was released in May 1990, it was so successful that Microsoft decided to change the primary application programming interface for the still-unreleased NT OS/2 (as it was then known) from an extended OS/2 API to an extended Windows API. This decision caused tension between Microsoft and IBM, and the collaboration ultimately fell apart. IBM continued OS/2 development alone, while Microsoft continued work on the newly-renamed Windows NT.

The first public demonstration of Windows NT, at the time called "Windows Advanced Server for LAN Manager", was at a developer conference in August 1991,and the product was formally announced at the Spring 1993 Comdex in Atlanta, Georgia.

Application programming interfaces in Windows NT are implemented as subsystems atop the undocumented Native API; it was this that allowed the late adoption of the Windows API. Windows NT was the first operating system to use Unicode internally. Windows NT introduced the Win32 API, a 32-bit implementation of the 16-bit Windows API. Most 16-bit Windows applications could be ported to the new system with minimal changes and a recompile. Win32 also provided native API support for many new features, such as networking and multithreading.

The project had a codename of just "NTOS", which is preserved in the filename of the Windows NT kernel, ntoskrnl.exe. Since it was targeted to become the next version of OS/2, a more official name of the project was "NT OS/2". This name is preserved up to now in some Windows NT driver development kit files.

System support:

NT was designed from the ground up to be portable to other platforms. All kernel and subsystem code was written in C and C++. Any differences in core hardware architecture that could not be resolved by a simple recompile (e.g., memory architecture, multi/uniprocessor support) were offloaded to the HAL.

Also, NT's boot architecture borrowed heavily from the ARC initiative, particularly on non-x86 platforms.

i860:

Originally, NT was targeted at the Intel i860 CPU, codenamed N10 (or "N-Ten"). However, the i860 was "horribly behind schedule", so the NT team used an emulator before i860 prototype systems designed in-house (code-named Dazzle) was available. Support for the other platforms followed later and no public release of NT for i860 systems was made. The rationale for targeting the i860 first was to improve portability and avoid producing an x86-centric design.

x86:

NT 3.1 supported the Intel x86 32-bit family (80386 and later). Compared to 16-bit Windows 3.x, NT's driver support was somewhat limited, but most 386 and 486 machines could run NT at least minimally.

MIPS:

Windows NT also supported the MIPS R4000 processor; specifically MIPS systems following the Advanced RISC Computing (ARC) specification..

Alpha:

Early in the NT beta cycle, support was added for the DEC Alpha processor. However, because the Alpha itself was not released, Microsoft's developers did not have access to production Alpha machines to develop on until shortly before NT shipped. Consequently, NT did not initially ship with Alpha support out of the box: the first packages of NT included a mail-in coupon to receive a free CD of NT 3.1 with Alpha support.

Application compatibility:

16-bit Windows:

Windows NT provided a 16-bit compatibility subsystem, called "Windows on Windows" (aka WOW), which allowed most Windows 3.x applications to run unmodified on NT. Applications which made direct access to hardware, or depended on DOS-level drivers, were not supported.

In NT 3.1, all 16-bit applications ran within a single WOW process. This meant that a single badly-behaving 16-bit application could shut down the WOW session (and any other 16-bit applications running). However, the operating system itself was insulated, so the WOW process could simply be killed and restarted — a significant step forward for Windows' stability.

32-bit Windows:

NT also introduced Win32, a 32-bit implementation of the Windows API. This permitted many 16-bit Windows applications to be recompiled for the system with minimal changes. Win32 also allowed the growing body of 16-bit Windows programmers to leverage their skills on the new system. The Win32 API was maintained (with some modifications) with Windows 95, further solidifying its role as Microsoft transitioned users off of the 16-bit platform.

Win32 is a comprehensive API, offering OS services ranging from memory management to UI access. NT prevents all user-level applications from directly accessing hardware. This increases system reliability, at the cost of performance. However, this also means that virtually all Win32 applications relied exclusively on the C/C++ Win32 API; the upshot is that porting such an application to another NT-supported system architecture (e.g., moving from x86 NT to MIPS NT) usually required no more than a recompile (some applications might require minor tweaking, such as if assumptions were made in code about endianness).

OS/2:

Though "NT OS/2" was finally released as "Windows NT", it is largely compatible with HPFS disk volumes and the x86 version supports character-mode 16-bit OS/2 applications. Many of the OS/2 APIs (particularly NetBIOS/LANMan networking APIs) already existed in almost identical forms in both 16-bit OS/2 and DOS/Windows, so these were incorporated into the Win32 API. For most 16-bit OS/2 programs, minimal code changes were necessary to recompile as NT console applications.

OS/2 and Windows also share the concept of Dynamic-Link Libraries (DLLs). Although the implementation varies somewhat between Windows and OS/2 DLLs, this additional similarity meant that even complex OS/2 applications could usually be converted to NT with little change to the overall design.

POSIX:

Windows NT 3.1 included a subsystem that was minimally POSIX-compatible. This was added largely to help spur sales in US government contracts, as many government agencies mandated POSIX compatibility for consideration.

Note that POSIX compatibility is an API-level requirement. That is, one POSIX operating system won't necessarily be able to execute binary files compiled for a different system, even though both are POSIX compliant. POSIX simply specifies that the source code should compile correctly for each system.

The POSIX subsystem in NT 3.1 primarily provided support for UNIX-style file system permissons and long filenames (including permitting filename characters that are otherwise illegal for Windows files, and denying some that are normally legal).

Internet Explorer:

Microsoft offered Internet Explorer starting with IE2, and released up to Internet Explorer 5.0 for Windows NT 3.x. Also, a IE 1.5 supported NT, but this patch was actually released after IE2 came out.

Editions:

* Windows NT Advanced Server

* Windows NT

Networking:

NT 3.1 included support for three network protocols: NBF (using the NetBEUI API), TCP/IP, and DLC.

NetBIOS Frames protocol:

At the time of NT's release, NetBIOS Frames protocol (NBF) was the most common protocol on Microsoft LAN Manager/IBM LAN Server networks. In NT 3.1, it was the only supported protocol for networking with legacy LAN Manager networks, as well as other NT systems. Using NBF, NT could participate in file/print sharing, and NT Advanced Server could act as a Domain Controller (even sharing DC duties with OS/2 LAN Manager servers).

TCP/IP:

Windows NT 3.1 was the first Windows operating system to include TCP/IP support as standard. The TCP/IP stack used was SpiderTCP, developed by Spider Systems. This was replaced in NT 3.5 with a new stack developed in-house.

The TCP/IP stack included WinSock and STREAMS support, but it was not supported for networking among Microsoft LAN Manager or NT systems. Also, DHCP was not available, so IP addresses had to be manually configured. Support for NBT, DHCP, and WINS was added in NT 3.5.

Data Link Control:

Data Link Control (DLC) was supported as a transport protocol for the purpose of communicating with network printers, such as those using an HP JetDirect interface. It could also be used by Microsoft SNA Server for communication with IBM mainframe systems.

Further reading:

G. Pascal Zachary (1994). "Show Stopper!: The Breakneck Race to Create Windows NT and the Next Generation at Microsoft", Free Press, ISBN 0029356717

References:

http://en.wikipedia.org

Windows 3.1x

2009-12-25T04:54:00.000-08:00

Windows 3.1x

Windows 3.1x is a line of operating systems produced by Microsoft for use on personal computers. The line began with Windows 3.1, which was released in March 1992 as a successor to Windows 3.0. Further editions were released between 1992 and 1994 until the line was superseded by Windows 95.

Editions:
Base version:
Windows 3.1 (originally codenamed Janus, of which two betas were published), released on April, 1992, includes a TrueType font system (and a set of highly legible fonts already installed), which effectively made Windows a serious desktop publishing platform for the first time. Similar functionality was available for Windows 3.0 through the Adobe Type Manager (ATM) font system from Adobe.

Windows 3.1 was designed to have high backward compatibility with older Windows platforms. As with Windows 3.0, version 3.1 had File Manager and Program Manager, but unlike all previous versions, Windows 3.1 and later support 32-bit disk access, can't run in real mode, and included Minesweeper instead of Reversi (though Reversi was included in some copies).

Versions with special font support:
A special version named Windows 3.1 for Central and Eastern Europe was released that allowed the use of Cyrillic and had fonts with diacritical marks characteristic of Central and Eastern European languages. Microsoft, which introduced its own codepage ('Windows-1250') and supported its use in violation of many countries' ISO standards (e.g., the official Polish codepage is ISO-8859-2, which was ignored by Microsoft but is supported by contemporary Internet Explorer versions). Similarly, Microsoft also released Windows 3.1J with support for the Japanese language, which shipped 1.46 million copies in its first year on the market (1993) in Japan.

Windows 3.11:
Microsoft also released an update for Windows 3.1 that (aside from installing new files) changes the Windows version displayed in "About" dialog boxes to 3.11. Thus, Windows 3.11 isn't a standalone version of Windows, but rather a software update from Windows 3.1, much like modern Windows service packs. For those who did not own Windows 3.1, full disk sets of Windows 3.11 were available at the time.

Windows 3.2:
Microsoft released a Simplified Chinese version of Windows for the Chinese market. The updated system identified itself as Windows 3.2. The update was limited to this language version, as it fixed only issues related to the complex writing system of the Chinese language
Windows 3.2 was generally sold by computer manufacturers with a ten-disk version of MS-DOS that also had Simplified Chinese characters in basic output and some translated utilities.

Modular Windows:
Modular Windows is a special version of Windows 3.1, designed to run on the Tandy Video Information System.

Windows for Workgroups:
Windows for Workgroups is an extension that allowed users to share their resources and to request those of others without a centralized authentication server. It used the SMB protocol over NetBIOS.

Windows for Workgroups 3.1:
Windows for Workgroups 3.1 (originally codenamed Winball and later Sparta), released in October 1992, features native networking support. Windows for Workgroups 3.1 is an extended version of Windows 3.1 that comes with SMB file sharing support via the NetBIOS based NBF and/or IPX network transport protocols, includes the Hearts card game, and introduced VSHARE.386, the Virtual Device Driver version of the SHARE.EXE Terminate and Stay Resident program

Windows for Workgroups 3.11:
Windows for Workgroups 3.11 (originally codenamed Snowball) was released on 11 August 1993,and shipped in November 1993.It supported 32-bit file access, full 32-bit network redirectors, and the VCACHE.386 file cache, shared between them. The standard execution mode of the Windows kernel was discontinued in Windows for Workgroups 3.11.

A Winsock package was required to support TCP/IP networking in Windows 3.x. Usually third-party packages were used, but in August 1994 Microsoft released an add-on package (codenamed Wolverine) that provided limited TCP/IP support in Windows for Workgroups 3.11.

Limited compatibility with the (then-new) 32-bit Windows API used by Windows NT was provided by another add-on package, Win32s. There was a rumor that Microsoft didn't want to increment any mainstream Windows 3.1x version to something like "Windows 3.2" because it could be scrambled with the Win32 API or otherwise distract consumers from upgrading to some 'real 32-bit OS' like the then-upcoming Windows 95 was.

Windows 3.x was superseded by the release Windows 95 in August of 1995.

On 9 July 2008, it was announced that as of 1 November 2008, Windows for Workgroups 3.11 for the embedded devices channel would no longer be made available for OEM distribution

Applications:
Windows 3.1x introduced new possibilities for applications, especially multimedia applications. During this era, Microsoft developed a new range of software that was implemented on this operating system, called Microsoft Home, Microsoft Bob being one of the programs.

Program Manager:
Program Manager was included in all versions of Windows from version 3.0 until Windows XP Service Pack 1. A non-operable icon library named progman.exe is included in Windows XP Service Pack 2, and the file was removed entirely from Windows Vista.

If Program Manager is started under Windows XP Service Pack 2 and later, it does not appear to run, but when a .grp file created for Windows 3.1 is processed, it converts the .grp file contents to a Start Menu folder.

Internet Explorer:
Microsoft released versions of Internet Explorer from 2.0 up to the first release of Internet Explorer 5.0 for Windows 3.1.

Promotion and reception:
Microsoft began a television advertising campaign for the first time on March 1, 1992. The advertisements, developed by Ogilvy & Mather, were designed to introduce a broader audience to Windows Windows 3.1 was shipped worldwide on April 6, 1992, and reached three million sales two months later. The year of Windows 3.1's release was successful for Microsoft, who were named the "Most Innovative Company Operating in the U.S." by Forbes Magazine, while Windows became the most widely-used GUI-based operating system.

Controversy:
DR-DOS compatibility:
The installer to the beta release used code that checked whether it was running on Microsoft-licensed DOS or another DOS operating system (such as DR-DOS). The code ran several functional tests that succeeded on MS-DOS and PC-DOS, but resulted in a technical support message on competing operating systems. If the system was not MS-DOS, the installer would fail. Digital Research, who owned DR-DOS, released a patch within weeks to allow the installer to continue. Microsoft disabled, but did not remove, this warning message for the final release of Windows 3.1. When Caldera Systems bought the DR-DOS from Novell, they brought a lawsuit against Microsoft over the AARD code, which was later settled

Legacy:
Windows 3.1 found a niche market as an embedded operating system after becoming obsolete in the PC world. Up until Microsoft discontinued 3.1 in November 2008, both Virgin Atlantic and Qantas employed it for some of the onboard entertainment systems on long-distance jets. It also sees continued use as an embedded OS in retail cash tills.

References:
http://en.wikipedia.org

Windows 3.0

2009-12-25T04:46:00.000-08:00

Windows 3.0

Windows 3.0 is the third major release of Microsoft Windows, and was released on 22 May 1990. It became the first widely successful version of Windows and a powerful rival to Apple Macintosh and the Commodore Amiga on the GUI front. It was followed by Windows 3.1.

Features:
Windows 3.0 succeeded Windows 2.1x and included a significantly revamped user interface as well as technical improvements to make better use of the memory management capabilities of Intel's 80286 and 80386 processors. Text-mode programs written for MS-DOS could be run within a window (a feature previously available in a more limited form with Windows/386 2.1), making the system usable as a crude multitasking base for legacy programs. However, this was of limited use for the home market, where most games and entertainment programs continued to require raw DOS access.

The MS-DOS Executive file manager/program launcher was replaced with the icon-based Program Manager and the list-based File Manager, thereby simplifying the launching of applications. The MS-DOS Executive is also included as an alternative to these. The Control Panel, previously available as a standard-looking applet, was re-modeled after the one in Mac OS. It centralized system settings, including limited control over the color scheme of the interface.

A number of simple applications were included, such as the text editor Notepad and the word processor Write (both inherited from earlier versions of Windows), a macro recorder (new; later dropped), the paint program Paintbrush (inherited but substantially improved), and a calculator (also inherited). The earlier Reversi game was complemented with a card game named Solitaire.

The Windows icons and graphics were redesigned to take advantage of VGA's 16-color mode. Earlier versions only supported eight colors.

Windows 3.0 includes a Protected/Enhanced mode which allows Windows applications to use more memory in a more painless manner than their DOS counterparts could. It can run in any of Real, Standard, or 386 Enhanced modes, and is compatible with any Intel processor from the 8086/8088 up to 80286 and 80386. Windows 3.0 tries to auto detect which mode to run in, although it can be forced to run in a specific mode using the switches: /r (real mode), /s ("standard" 286 protected mode) and /3 (386 enhanced protected mode) respectively. This was the first version to run Windows programs in protected mode, although the 386 enhanced mode kernel was an enhanced version of the protected mode kernel in Windows/386.

Due to this backward compatibility, Windows 3.0 applications also must be compiled in a 16-bit environment, without ever using the full 32-bit capabilities of the 386 CPU.

A "multimedia" version, Windows 3.0 with Multimedia Extensions 1.0, was released several months later. This was bundled with "multimedia upgrade kits", comprising a CD-ROM drive and a sound card, such as the Creative Labs Sound Blaster Pro. This version was the precursor to the multimedia features available in Windows 3.1 and later, and was part of the specification for Microsoft's specification for the Multimedia PC.

Windows 3.0 was the last version of Windows to advertise 100% compatibility with older Windows applications. This only applies to real mode.

System requirements:
The official system requirements for Windows 3.0:

* 8086/8088 processor or better
* 640K conventional memory
* a hard disk with 6-7MB of free space
* CGA/EGA/VGA/Hercules/8514/A graphics and an appropriate and compatible monitor

Also, a Microsoft-compatible mouse is recommended.

Memory modes:
Windows 3.0 was the only version of Windows that could be run in three different memory modes:

* Real mode, intended for older computers with a CPU below Intel 80286, and corresponding to its real mode;
* Standard mode, intended for computers with an 80286 processor, and corresponding to its protected mode;
* 386 Enhanced mode, intended for newer computers with an Intel 80386 processor or above, and corresponding to its protected mode and virtual 8086 mode.

Real mode primarily existed as a way to run Windows 2.x applications. It was removed in Windows 3.1x. Almost all applications designed for Windows 3.0 had to be run in Standard or 386 Enhanced modes. However, it was necessary to load Windows 3.0 in Real mode to run SWAPFILE.EXE, which allowed users to change virtual memory settings.

Standard mode was used most often as its requirements were more in-line with an average PC of that era – a 286 processor with at least 1MB of memory. Incidentally, not all 286 and 386 computers remapped memory between 640 KB (the upper limit of Conventional memory) and 1 MB as extended memory — some did not show memory between 640 KB and 1 MB at all — so on some systems with 1 MB of RAM, there is no extended memory and memory was limited to 640 KB. On such a system, Windows was limited to real mode. Many 386 computers ran Windows 3.0 in Standard mode due to a lack of memory.

386 Enhanced mode implemented all the benefits of Standard mode, plus 32-bit addressing and paging for faster memory access, and virtual 8086 mode for safer execution of MS-DOS programs: each of them now ran in a virtual machine. In the previous modes, multiple MS-DOS programs could only be run in full-screen, and only the program currently active was executing; but in 386 enhanced mode, they could be run simultaneously in separate windows. This mode required a 386 processor and 1MB of extended memory (in addition to the base 640KB) – beyond the specifications of most PCs sold in 1990.

Multimedia Extensions:
The Multimedia Extensions were released in autumn 1991 to support sound cards, as well as CD-ROM drives, which were then becoming increasingly available. The Multimedia Extensions were released to Original Equipment Manufacturers (OEMs), mainly CD-ROM drive and sound card manufacturers, and added basic multimedia support for audio input and output and a CD audio player application to Windows 3.0. The Multimedia Extensions' new features were not available in Windows 3.0 real mode. Windows 3.1x would later incorporate many of its features. Microsoft developed the Windows Sound System sound card specification to complement these extensions.

The MME API was the first universal and standardized Windows audio API. Wave sound events played in Windows (up to Windows XP) and MIDI I/O use MME. The devices listed in the Multimedia/Sounds and Audio control panel applet represent the MME API of the sound card driver.

MME lacks channel mixing, so only one audio stream can be rendered at a time. MME supports sharing the audio device for playback between multiple applications starting with Windows XP, up to two channels of recording, 16-bit audio bit depth and sampling rates of up to 44.1 kHz with all the audio being mixed and sampled to 44.1 kHz.

Marketing:
This version of Windows was the first to be pre-installed on hard drives by PC-compatible manufacturers. Zenith Data Systems had previously shipped all of its computers with Windows 1.0 or later 2.x on diskettes but committed early in the development of Windows 3.0 to shipping it pre-installed. Indeed, the Zenith division had pushed Microsoft hard to develop the graphical user interface because of Zenith's direct competition with Apple in the college & university market.

Windows 3.0 was not available as a run-time version, as was the case with its predecessors. A limited-use version of Windows 2.x was often bundled with other applications (i.e. Ami Pro) due to the low market penetration of Windows itself. Starting with Windows 3.0, Microsoft required that customers obtain a copy of Windows (in addition to obtaining DOS), in order to be able to use Windows applications.

References:
http://en.wikipedia.org

Windows 2.1x

2009-12-25T04:43:00.000-08:00

Windows 2.1x

Windows 2.1x is a family of Microsoft Windows graphical user interface-based operating environments.

Less than a year after the release of Windows 2.0, Windows/286 2.10 and Windows/386 2.10 were released on 27 May 1988. These versions can take advantage of the specific features of the Intel 80286 and Intel 80386 processors.

Editions:
Two editions of Windows 2.10 were released, both of which could take advantage of the Intel processor for which they were designed.

Windows/286:
Windows/286 takes advantage of the HMA to increase the memory available to Windows programs. It introduced the himem.sys DOS driver for this purpose. It also includes support for several EMS boards, although this support is not related to the 80286 processor. The segmented nature of Windows programs is quite suited to the usage of EMS, as portions of code and data can be made visible in the first megabyte of memory accessible to real-mode programs only when the program using them is given control. Microsoft encouraged users to configure their computers with only 256KB of main memory, leaving the address space from 256-640KB available for dynamic mapping of EMS memory.

Despite its name, Windows/286 was fully operational on an 8088 or 8086 processor. Windows/286 would simply not use the high memory area since none exist on an 8086-class processor; however, EMS could still be used, if present. A few PC vendors shipped Windows/286 with 8086 hardware; an example was IBM's PS/2 Model 25, which had an option to ship with a "DOS 4.00 and Windows kit" for educational markets, which included word processing and presentation software useful for students, which resulted in some confusion when purchasers of this system received a box labelled Windows/286 with a machine that was definitely less than an 80286.

Windows/386:
Windows/386 is much more advanced. It introduced a protected mode kernel, above which the GUI and applications run as a virtual 8086 mode task. It allows several MS-DOS programs to run in parallel in "virtual 8086" CPU mode, rather than always suspending background applications. (Windows applications could already run in parallel through cooperative multitasking.) Each DOS application can use as much low memory as is available before Windows is started, minus a few kilobytes of overhead. Windows/386 also provides EMS emulation, using the memory management features of the 80386 to make RAM beyond 640K behave like the banked memory previously only supplied by add-in cards and used by popular DOS applications. (By overwriting the WIN200.BIN file with COMMAND.COM, it is possible to use the EMS emulation in DOS without starting the Windows GUI.) There is no disk-based virtual memory, so multiple DOS programs have to fit inside the available physical memory; therefore, Microsoft suggested buying additional memory and cards if necessary.

Neither of these versions work with DOS memory managers like CEMM or QEMM or with DOS extenders, which have their own extended memory management and run in protected mode as well. This was remedied in version 3.0, which is compatible with VCPI in "standard mode" and with DPMI in "386 enhanced" mode. Windows 3.0 also has the capability of using the DWEMM Direct Write Enhanced Memory Module. This is what enables the far faster and sleek graphical user interface.

Windows 2.11:
In March 1989, Windows 2.11 was released in Windows/286 and Windows/386 editions, with some minor changes in memory management, AppleTalk support and faster printing and updated printer drivers.

Windows 2.11 was superseded by Windows 3.0 in May 1990.

References:
http://en.wikipedia.org

Windows 2.0

2009-12-25T04:41:00.000-08:00

Windows 2.0

Windows 2.0 was a 16-bit Microsoft Windows graphical user interface-based operating environment that superseded Windows 1.0. Windows 2.0 was supplemented by Windows/286 and Windows/386 in 1988. Windows 2.0, Windows/286 and Windows/386 were superseded by Windows 3.0 in May 1990.

History:
Application support:
The first Windows versions of Microsoft Word and Microsoft Excel ran on Windows 2.0. Third-party developer support for Windows increased substantially with this version (some shipped the Windows Runtime software with their applications, for customers who had not purchased the full version of Windows). However, most developers still maintained DOS versions of their applications, as Windows users were still a distinct minority of their market.

Applications shipping with Windows 2.0:

* CALC.EXE
* CALENDAR.EXE
* CARDFILE.EXE
* CLIPBRD.EXE
* CLOCK.EXE
* CONTROL.EXE
* CVTPAINT.EXE
* MSDOS.EXE
* MSDOSD.EXE
* NOTEPAD.EXE
* PAINT.EXE
* PRACTICE.WRI
* REVERSI.EXE
* TERMINAL.EXE
* WRITE.EXE

AT&T:
Windows 2.0 was packaged with AT&T Computers as test software for many educational institutions. This variation of Windows 2.0 has "plug 'n' play" capabilities

Legal conflict with Apple:
On 17 March 1988, Apple filed suit against Microsoft and Hewlett-Packard, accusing them of violating copyrights Apple held on the Macintosh System Software. Apple claimed the "look and feel" of the Macintosh operating system, taken as a whole, was protected by copyright and that Windows 2.0 violated this copyright by looking extremely similar to it.

Features:
Windows 2.0 allowed application windows to overlap each other, unlike its predecessor Windows 1.0, which could only display tiled windows. Windows 2.0 also introduced more sophisticated keyboard-shortcuts and the terminology of "Minimize" and "Maximize", as opposed to "Iconize" and "Zoom" in Windows 1.0.

References:
http://en.wikipedia.org/

Windows 1.0

2009-12-25T04:37:00.000-08:00

Windows 1.0

Windows 1.0 is a 16-bit graphical operating environment that was released on 20 November 1985. It was Microsoft's first attempt to implement a multi-tasking graphical user interface-based operating environment on the PC platform. Windows 1.0 was the very first version of Windows launched. It was succeeded by Windows 2.0.

History:
The first release version is actually numbered 1.01. It was rumored that version 1.00 was actually released but quickly pulled due to a severe flaw having to do with keyboard input. However, this rumor has now been disproved.

Version 1.02, released in May 1986, was international and had editions in several European languages. Version 1.03, released in August 1986, was for the US- and international market, with enhancements making it consistent with the international release. It included drivers for European keyboards and additional screen and printer drivers. Version 1.04, released in April 1987, added support for the VGA graphics adapters of the new IBM PS/2 computers. At the same time, Microsoft and IBM announced the introduction of OS/2 and its graphical OS/2 Presentation Manager, which were supposed to ultimately replace both MS-DOS and Windows.

Windows 1.0 was superseded in November 1987, with the release of Windows 2.0. Windows 1.0 was supported by Microsoft for sixteen years, until 31 December 2001. Windows 1.0 was one of the longest supported operating systems of the Microsoft Windows family of operating systems.

Installation media:
Windows 1.0 was only available on floppy disks. The user had to have DOS to install. It was the same with all versions of Windows up to and including Windows 95, which was still available on diskettes (but no longer required DOS to be installed first).

Competition:
The history of Windows dates back to September 1981, when the project named "Interface Manager" was started. It was first presented to the public in 10 November 1983, renamed to "Microsoft Windows"; the two years of delay before release led to charges that it was "vaporware". The initially announced version of Windows had features so much resembling the Macintosh interface that Microsoft had to change many of them: overlapping windows, although supported by the GUI engine, weren't allowed for exactly this reason. The announcement of Windows' imminent arrival in 1985 probably did not help the sales of VisiCorp's VisiOn environment which debuted at the same time. However, even when finally released, Windows 1.0 aroused little interest.

Another GUI for the PC platform at the time was GEM. It used more aspects from the Macintosh GUI, for example the trash can concept (which Microsoft would later employ in future Windows releases) and more generally the desktop interaction. GEM was eventually used as the standard GUI for the Atari's ST range of 68k-based computers, which were sometimes referred to as Jackintoshes (the company being run by Jack Tramiel). GEM's resemblance to the Macintosh OS later caused legal trouble for the manufacturer, Digital Research, who was obliged to seriously cripple the desktop's appearance and functionality (applications were not affected).

GEM was not multitasking, so users had to close one program in order to run another one. Collections of related programs, like GEM Draw, had tricky File menu items like Close (to Edit) to facilitate switching.

An alternative multitasker released shortly before was DESQview, a successor of IBM's failed TopView from 1984. It did not have graphical capabilities initially, but is able to multitask DOS applications in windows as long as they are well-behaved or have a specially written "loader" to fix them on the fly.

Windows 1.0 market share grew very slowly, as there was no killer app (market-dominating software) that required the graphical shell. The killer apps at the time were generally only available on the Apple Macintosh platform (this statement was true even of Microsoft's Mac-OS-only Microsoft Office).

The Macintosh remained the platform of choice especially for high-end graphics and desktop publishing (DTP). Although Aldus PageMaker shipped in January 1987 with a Windows executable, it remained but a curiosity due to poor support relative to the Mac version, and a steep $795 price tag.

PC-based DTP remained out of the reach of most Windows users until the release of $99 Serif PagePlus 1.0 in 1991. PagePlus won considerable praise from the prestigious Seybold Reports, not only for being the first sub-$100 DTP package capable of CMYK color separations but also because Serif backed up their customers with free 24-hour support. Nearly every desktop publishing magazine shootout review would include both programs side by side despite the price differences. In the real world however, the lack of a Mac version meant few prepress service bureaus would accept PC data or PC PostScript files. Corel Draw 1.0, Micrographix Picture Publisher, Paint Shop Pro, and Cool Edit also provided a Windows-only focus and provided capabilities previously only found in expensive applications.

Other shell programs for MS-DOS include Norton Commander, PC Tools, XTree. DOS Shell, and DOS Menu (in MS-DOS version 4.0). These applications attempted to be organizational and menu-driven tools, and did not try at all to be a 'desktop' shell.

Features:
Windows 1.0 offers limited multitasking of existing MS-DOS programs and concentrates on creating an interaction paradigm (cf. message loop), an execution model and a stable API for native programs for the future. Due to Microsoft's extensive support for backward compatibility, it is not only possible to execute Windows 1.0 binary programs on current versions of Windows to a large extent, but also to recompile their source code into an equally functional "modern" application with just limited modifications.

Windows 1.0 is often regarded as a "front-end to the MS-DOS operating system", a description which has also been applied to subsequent versions of Windows. Windows 1.0 is an MS-DOS program. Windows 1.0 programs can call MS-DOS functions, and GUI programs are run from .exe files just like MS-DOS programs. However, Windows .exe files had their own "new executable" (NE) file format, which only Windows could process and which, for example, allowed demand-loading of code and data. Applications were supposed to handle memory only through Windows' own memory management system, which implemented a software-based virtual memory scheme allowing for applications larger than available RAM.

Because graphics support in MS-DOS is extremely limited, MS-DOS applications have to go to the bare hardware (or sometimes just to the BIOS) to get work done. Therefore, Windows 1.0 included original device drivers for video cards, a mouse, keyboards, printers and serial communications, and applications were supposed to only invoke APIs built upon these drivers. However, this extended to other APIs such as file system management functions. In this sense, Windows 1.0 was designed to be extended into a full-fledged operating system, rather than being just a graphics environment used by applications. Indeed, Windows 1.0 is a "DOS front-end" and cannot operate without a DOS environment (it uses, for example, the file-handling functions provided by DOS.) The level of replacement increases in subsequent versions.

The system requirements for Windows 1.0 constituted CGA/Hercules/EGA (listed as "Monochrome or color monitor"), MS-DOS 3.1, 384K RAM (512KB recommended), and 2 double-sided disk drives or a hard drive.
Windows 1.0 runs a shell program known as MS-DOS Executive. Other supplied programs are Calculator, Calendar, Cardfile, Clipboard viewer, Clock, Control Panel, Notepad, Paint, Reversi, Terminal, and Write.

Windows 1.0 does not allow overlapping windows, due to Apple Computer owning this feature. Instead all windows are tiled. Only dialog boxes can appear over other windows.

Windows 1.0 executables, while having the same .exe extension and initial file header as MS-DOS programs, do not contain the so-called MS-DOS stub which prints the "This program requires Microsoft Windows" message and exits when the program is run outside of Windows. Instead, the file header was formatted in such a way as to make DOS reject the executable with a "program too large to fit in memory" error message.

From the beginning, Windows was intended to multitask programs (although this originally only applied to native applications and for many versions the multitasking was co-operative, rather than preemptive).

Originally Windows was designed to have the pull-up menus at the bottom of windows, as it was common with the DOS programs of the time; however, this was changed before the first release.

References:
http://en.wikipedia.org/

Microsoft Windows

2009-12-25T04:19:00.000-08:00

Microsoft Windows

Introduction:
Microsoft Windows is a series of software operating systems and graphical user interfaces produced by Microsoft. Microsoft first introduced an operating environment named Windows in November 1985 as an add-on to MS-DOS in response to the growing interest in graphical user interfaces (GUIs). Microsoft Windows came to dominate the world's personal computer market, overtaking Mac OS, which had been introduced previously. At the 2004 IDC Directions conference, it was stated that Windows had approximately 90% of the client operating system market. The most recent client version of Windows is Windows Vista; the most recent server version is Windows Server 2008. Vista's successor, Windows 7 (currently a public release candidate) is slated to be released prior to the 2009 holiday season

History:
Microsoft has taken two parallel routes in its operating systems. One route has been for the home user and the other has been for the professional IT user. The dual routes have generally led to home versions having greater multimedia support and less functionality in networking and security, and professional versions having inferior multimedia support and better networking and security.

The first version of Microsoft Windows, version 1.0, released in November 1985, lacked a degree of functionality and achieved little popularity, and was to compete with Apple’s own operating system.[citation needed] Windows 1.0 is not a complete operating system; rather, it extends MS-DOS. Microsoft Windows version 2.0 was released in November, 1987 and was slightly more popular than its predecessor. Windows 2.03 (release date January 1988) had changed the OS from tiled windows to overlapping windows. The result of this change led to Apple Computer filing a suit against Microsoft alleging infringement on Apple's copyrights

Microsoft Windows version 3.0, released in 1990, was the first Microsoft Windows version to achieve broad commercial success, selling 2 million copies in the first six months.It featured improvements to the user interface and to multitasking capabilities. It received a facelift in Windows 3.1, made generally available on March 1, 1992. Windows 3.1 support ended on December 31, 2001.

In July 1993, Microsoft released Windows NT based on a new kernel. NT was considered to be the professional OS and was the first Windows version to utilize preemptive multitasking.[citation needed]. Windows NT would later be retooled to also function as a home operating system, with Windows XP.

On August 24, 1995, Microsoft released Windows 95, a new, and major, consumer version that made further changes to the user interface, and also used preemptive multitasking. Windows 95 was designed to replace not only Windows 3.1, but also Windows for Workgroups, and MS-DOS. It was also the first Windows operating system to use Plug and Play capabilities. The changes Windows 95 brought to the desktop were revolutionary, as opposed to evolutionary, such as those in Windows 98 and Windows Me. Mainstream support for Windows 95 ended on December 31, 2000 and extended support for Windows 95 ended on December 31, 2001.

The next in the consumer line was Microsoft Windows 98 released on June 25, 1998. It was substantially criticized for its slowness and for its unreliability compared with Windows 95, but many of its basic problems were later rectified with the release of Windows 98 Second Edition in 1999.[citation needed] Mainstream support for Windows 98 ended on June 30, 2002 and extended support for Windows 98 ended on July 11, 2006.

As part of its "professional" line, Microsoft released Windows 2000 in February 2000. The consumer version following Windows 98 was Windows Me (Windows Millennium Edition). Released in September 2000, Windows Me implemented a number of new technologies for Microsoft: most notably publicized was "Universal Plug and Play."

In October 2001, Microsoft released Windows XP, a version built on the Windows NT kernel that also retained the consumer-oriented usability of Windows 95 and its successors. This new version was widely praised in computer magazines.It shipped in two distinct editions, "Home" and "Professional", the former lacking many of the superior security and networking features of the Professional edition. Additionally, the first "Media Center" edition was released in 2002,[20] with an emphasis on support for DVD and TV functionality including program recording and a remote control. Mainstream support for Windows XP ended on April 14, 2009. Extended support will continue until April 8, 2014.

In April 2003, Windows Server 2003 was introduced, replacing the Windows 2000 line of server products with a number of new features and a strong focus on security; this was followed in December 2005 by Windows Server 2003 R2.

On January 30, 2007 Microsoft released Windows Vista. It contains a number of new features, from a redesigned shell and user interface to significant technical changes, with a particular focus on security features. It is available in a number of different editions, and has been subject to some criticism.

Versions:
The term Windows collectively describes any or all of several generations of Microsoft operating system products. These products are generally categorized as follows:

Early versions:
The history of Windows dates back to September 1981, when the project named "Interface Manager" was started. It was announced in November 1983 (after the Apple Lisa, but before the Macintosh) under the name "Windows", but Windows 1.0 was not released until November 1985. The shell of Windows 1.0 was a program known as the MS-DOS Executive. Other supplied programs are Calculator, Calendar, Cardfile, Clipboard viewer, Clock, Control Panel, Notepad, Paint, Reversi, Terminal, and Write. Windows 1.0 does not allow overlapping windows, due to Apple Computer owning this feature. Instead all windows are tiled. Only dialog boxes can appear over other windows.

Windows 2.0 was released in October 1987 and featured several improvements to the user interface and memory management. Windows 2.0 allowed application windows to overlap each other and also introduced more sophisticated keyboard-shortcuts. It could also make use of expanded memory.

Windows 2.1 was released in two different flavors: Windows/386 employed the 386 virtual 8086 mode to multitask several DOS programs, and the paged memory model to emulate expanded memory using available extended memory. Windows/286 (which, despite its name, would run on the 8086) still ran in real mode, but could make use of the high memory area.

The early versions of Windows were often thought of as simply graphical user interfaces, mostly because they ran on top of MS-DOS and used it for file system services. However, even the earliest 16-bit Windows versions already assumed many typical operating system functions; notably, having their own executable file format and providing their own device drivers (timer, graphics, printer, mouse, keyboard and sound) for applications. Unlike MS-DOS, Windows allowed users to execute multiple graphical applications at the same time, through cooperative multitasking. Windows implemented an elaborate, segment-based, software virtual memory scheme, which allowed it to run applications larger than available memory: code segments and resources were swapped in and thrown away when memory became scarce, and data segments moved in memory when a given application had relinquished processor control, typically waiting for user input.

Windows 3.0 and 3.1:
Windows 3.0 (1990) and Windows 3.1 (1992) improved the design, mostly because of virtual memory and loadable virtual device drivers (VxDs) which allowed them to share arbitrary devices between multitasked DOS windows.[citation needed] Also, Windows applications could now run in protected mode (when Windows was running in Standard or 386 Enhanced Mode), which gave them access to several megabytes of memory and removed the obligation to participate in the software virtual memory scheme. They still ran inside the same address space, where the segmented memory provided a degree of protection, and multi-tasked cooperatively. For Windows 3.0, Microsoft also rewrote critical operations from C into assembly, making this release faster and less memory-hungry than its predecessors.[citation needed] With the introduction of the Windows for Workgroups 3.11, Windows was able to bypass DOS for file management operations using 32-bit file access

Windows 95, 98, and Me:
Windows 95 was released in 1995, featuring a new user interface, supported long file names, could automatically detect and configure installed hardware (plug and play), natively ran 32-bit applications, and featured several technological improvements that increased its stability over Windows 3.1. Windows 95 uses pre-emptive multitasking and runs each 32-bit application in a separate address space. This makes it harder for a single buggy application to crash the whole system. It was still not a secure multi-user operating system like Windows NT as a strict separation between applications was not enforced by the kernel. The API was a subset of the Win32 API supported by Windows NT, notably lacking support for Unicode and functions related to security. Windows 95 was now bundled together with MS-DOS 7.0, however its role was mostly delegated to that of a boot loader.

There were several releases of Windows 95; the first in 1995, with Service Pack 1 following in December which included Internet Explorer 2.0. Subsequent versions were only available with the purchase of a new computer and were called OEM Service Releases. OSR1 was equivalent to Windows 95 with SP1. OSR2 (also called Windows 95 B) included support for FAT32 and UDMA and shipped with Internet Explorer 3. OSR 2.1 included basic support for USB and OSR 2.5 (also called Windows 95C) shipped with Internet Explorer 4.0.

Microsoft's next release was Windows 98 in 1998. Microsoft released a second version of Windows 98 in 1999, named Windows 98 Second Edition (often shortened to Windows 98 SE).

In 2000, Microsoft released Windows Me (Me standing for Millennium Edition), which used the same core as Windows 98 but adopted some aspects of Windows 2000 and removed the "boot in DOS mode" option. It also added a new feature called System Restore, allowing the user to set the computer's settings back to an earlier date. Me is also the last DOS-based Windows release which does not include Microsoft Product Activation.

Windows NT family:
The NT family of Windows systems was fashioned and marketed for higher reliability business use, and was unencumbered by any Microsoft DOS patrimony. The first release was MS Windows NT 3.1 (1993, numbered "3.1" to match the consumer Windows version, which was followed by NT 3.5 (1994), NT 3.51 (1995), NT 4.0 (1996), and Windows 2000 (2000). 2000 is the last NT-based Windows release which does not include Microsoft Product Activation. NT 4.0 was the first in this line to implement the "Windows 95" user interface (and the first to include Windows 95’s built-in 32-bit runtimes). Microsoft then moved to combine their consumer and business operating systems with Windows XP, coming in both home and professional versions (and later niche market versions for tablet PCs and media centers); they also diverged release schedules for server operating systems. Windows Server 2003, released a year and a half after Windows XP, brought Windows Server up to date with MS Windows XP. After a lengthy development process, Windows Vista was released toward the end of 2006, and its server counterpart, Windows Server 2008 was released in early 2008. In 2009, Windows 7 and Windows Server 2008 R2 entered beta. Microsoft plans to release Windows 7 in late 2009 or early 2010.

Windows CE, Microsoft’s offering in the mobile and embedded markets, is also a true 32-bit operating system that offers various services for all sub-operating workstations.

64-bit operating systems:
Windows NT included support for several different platforms before the x86-based personal computer became dominant in the professional world. Versions of NT from 3.1 to 4.0 variously supported PowerPC, DEC Alpha and MIPS R4000, some of which were 64-bit processors, although the operating system treated them as 32-bit processors.

With the introduction of the Intel Itanium architecture, which is referred to as IA-64, Microsoft released new versions of Windows to support it. Itanium versions of Windows XP and Windows Server 2003 were released at the same time as their mainstream x86 (32-bit) counterparts. On April 25, 2005, Microsoft released Windows XP Professional x64 Edition and x64 versions of Windows Server 2003 to support the AMD64/Intel64 (or x64 in Microsoft terminology) architecture. Microsoft dropped support for the Itanium version of Windows XP in 2005. Windows Vista is the first end-user version of Windows that Microsoft has released simultaneously in x86 and x64 editions. Windows Vista does not support the Itanium architecture. The modern 64-bit Windows family comprises AMD64/Intel64 versions of Windows Vista, and Windows Server 2008, in both Itanium and x64 editions. Windows Server 2008 R2 drops the 32-bit version, although Windows 7 does not.

Windows CE:
Windows CE (officially known as Windows Embedded), is an edition of Windows that runs on minimalistic computers, like satellite navigation systems, and uncommonly mobile phones. Windows Embedded runs as CE, rather than NT, which is why it should not be mistaken for Windows XP Embedded, which is NT. Windows CE was used in the Sega Dreamcast along with Sega's own proprietary OS for the console.

Security:
Security has been a hot topic with Windows for many years, and even Microsoft itself has been the victim of security breaches.[citation needed] Consumer versions of Windows were originally designed for ease-of-use on a single-user PC without a network connection, and did not have security features built in from the outset.

Windows NT and its successors are designed for security (including on a network) and multi-user PCs, but were not initially designed with Internet security in mind as much since, when it was first developed in the early 1990s, Internet use was less prevalent.

These design issues combined with flawed code (such as buffer overflows) and the popularity of Windows means that it is a frequent target of computer worm and virus writers. In June 2005, Bruce Schneier’s Counterpane Internet Security reported that it had seen over 1,000 new viruses and worms in the previous six months.

Microsoft releases security patches through its Windows Update service approximately once a month (usually the second Tuesday of the month), although critical updates are made available at shorter intervals when necessary.In Windows 2000 (SP3 and later), Windows XP and Windows Server 2003, updates can be automatically downloaded and installed if the user selects to do so. As a result, Service Pack 2 for Windows XP, as well as Service Pack 1 for Windows Server 2003, were installed by users more quickly than it otherwise might have been

Windows Defender:
On January 6, 2005, Microsoft released a beta version of Microsoft AntiSpyware, based upon the previously released Giant AntiSpyware. On February 14, 2006, Microsoft AntiSpyware became Windows Defender with the release of beta 2. Windows Defender is a freeware program designed to protect against spyware and other unwanted software. Windows XP and Windows Server 2003 users who have genuine copies of Microsoft Windows can freely download the program from Microsoft's web site, and Windows Defender ships as part of Windows Vista.

Third-party analysis:
In an article based on a report by Symantec, internetnews.com has described Microsoft Windows as having the "fewest number of patches and the shortest average patch development time of the five operating systems it monitored in the last six months of 2006." And the number of vulnerabilities found in Windows has significantly increased— Windows: 12+, Red Hat + Fedora: 2, Mac OS X: 1, HP-UX: 2, Solaris: 1.

A study conducted by Kevin Mitnick and marketing communications firm Avantgarde in 2004 found that an unprotected and unpatched Windows XP system with Service Pack 1 lasted only 4 minutes on the Internet before it was compromised, and an unprotected and also unpatched Windows Server 2003 system was compromised after being connected to the internet for 8 hours.However, it is important to note that this study does not apply to Windows XP systems running the Service Pack 2 update (released in late 2004), which vastly improved the security of Windows XP. The computer that was running Windows XP Service Pack 2 was not compromised. The AOL National Cyber Security Alliance Online Safety Study of October 2004 determined that 80% of Windows users were infected by at least one spyware/adware product. Much documentation is available describing how to increase the security of Microsoft Windows products. Typical suggestions include deploying Microsoft Windows behind a hardware or software firewall, running anti-virus and anti-spyware software, and installing patches as they become available through Windows Update.

Windows Lifecycle Policy:
Microsoft has stopped releasing updates and hotfixes for many old Windows operating systems, including all versions of Windows 9x, and earlier versions of Windows NT. Windows versions prior to Windows 2000 are no longer supported. No new updates are created for unsupported versions of Windows.

Emulation software:
Emulation allows the use of some Windows applications without using Microsoft Windows. These include:

* Wine — a free and open source software implementation of the Windows API, allowing one to run many Windows applications on x86-based platforms, including Linux. Wine is technically not an emulator but a "compatibility layer";while an emulator effectively ‘pretends’ to be a different CPU, Wine instead makes use of Windows-style APIs to ‘simulate’ the Windows environment directly.
o CrossOver — A Wine package with licensed fonts. Its developers are regular contributors to Wine, and focus on Wine running officially supported applications.
o Cedega — TransGaming Technologies' proprietary fork of Wine, designed specifically for running games written for Microsoft Windows under Linux. A version of Cedega known as Cider is used by some video game publishers to allow Windows games to run on Mac OS X. Since wine was licensed under the LGPL Cedega has been unable to port the improvements made to wine to their proprietary codebase.
o Darwine — A bundling of Wine to the PowerPC Macs running OS X by running wine on top of QEMU. Intel Macs use the same Wine as other *NIX x86 systems.
* ReactOS — An open-source OS that is intended to run the same software as Windows, originally designed to imitate Windows NT 4.0, now aiming at Windows XP compatibility. It has been in the development stage since 1996.

References:
http://en.wikipedia.org

Microsoft History

2009-12-25T03:39:00.000-08:00

Microsoft History

Microsoft History

Introduction:
Microsoft Corporation is an American-based multinational computer technology corporation that develops, manufactures, licenses, and supports a wide range of software products for computing devices.Headquartered in Redmond, Washington, USA, its most profitable products are the Microsoft Windows operating system and the Microsoft Office suite of productivity software.

Originally founded to develop and sell BASIC interpreters for the Altair 8800, Microsoft rose to dominate the home computer operating system market with MS-DOS in the mid-1980s, followed by the Windows line of operating systems. Its products have all achieved near-ubiquity in the desktop computer market. One commentator notes that Microsoft's original mission was "a computer on every desk and in every home, running Microsoft software." Microsoft possesses footholds in other markets, with assets such as the MSNBC cable television network, the MSN Internet portal, and the Microsoft Encarta multimedia encyclopedia. The company also markets both computer hardware products such as the Microsoft mouse as well as home entertainment products such as the Xbox, Xbox 360, Zune and MSN TV. The company's initial public stock offering (IPO) was in 1986; the ensuing rise of the company's stock price has made four billionaires and an estimated 12,000 millionaires from Microsoft employees.

Throughout its history the company has been the target of criticism, including monopolistic business practices and anti-competitive strategies including refusal to deal and tying. The U.S. Justice Department and the European Commission, among others, have ruled against Microsoft for various antitrust violations.

Known for what is generally described as a developer-centric business culture,[dubious – discuss] Microsoft has historically given customer support over Usenet newsgroups and the World Wide Web, and awards Microsoft MVP status to volunteers who are deemed helpful in assisting the company's customers

History:
1975–1984: Founding:
Following the launch of the Altair 8800, William Henry Gates III, (known as Bill Gates) called the creators of the new microcomputer, Micro Instrumentation and Telemetry Systems (MITS), offering to demonstrate an implementation of the BASIC programming language for the system. After the demonstration, MITS agreed to distribute Altair BASIC. Gates left Harvard University, moved to Albuquerque, New Mexico where MITS was located, and founded Microsoft there. The company's first international office was founded on November 1, 1978, in Japan, entitled "ASCII Microsoft" (now called "Microsoft Japan"). On January 1, 1979, the company moved from Albuquerque to a new home in Bellevue, Washington. Steve Ballmer joined the company on June 11, 1980, and later succeeded Bill Gates as CEO.

Among pre-IBM-PC products were the software package TASC (The AppleSoft Compiler), which compiled a BASIC program into Apple machine language, and the hardware Microsoft Softcard, an add-on Z80 processor card for the Apple II and compatible computers which allowed the use of the CP/M operating system instead of Applesoft and Apple DOS.

DOS (Disk Operating System) was the operating system that brought the company its first real success. On August 12, 1981, after negotiations with Digital Research failed, IBM awarded a contract to Microsoft to provide a version of the CP/M operating system, which was set to be used in the upcoming IBM Personal Computer (PC). For this deal, Microsoft purchased a CP/M clone called 86-DOS from Seattle Computer Products, which IBM renamed to PC-DOS. Later, the market saw a flood of IBM PC clones after Columbia Data Products successfully cloned the IBM BIOS, and by aggressively marketing MS-DOS to manufacturers of IBM-PC clones, Microsoft rose from a small player to one of the major software vendors in the home computer industry. The company expanded into new markets with the release of the Microsoft Mouse in 1983, as well as a publishing division named Microsoft Press.

1985–1994: IPO, OS/2 and Windows:
In August 1985, Microsoft and IBM partnered in the development of a different operating system called OS/2. On November 20, 1985, Microsoft released its first retail version of Microsoft Windows, originally a graphical extension for its MS-DOS operating system. On March 13, 1986 the company went public with an initial public offering (IPO), with a starting initial offering price of $21.00 and ending at the first day of trading as at US $28.00. The ensuing rise of the stock price has made four billionaires and an estimated 12,000 millionaires from Microsoft employees. In 1987, Microsoft eventually released their first version of OS/2 to OEMs.

IPO:
Microsoft's Initial Public Offering occurred on March 14, 1986. The stock closed at $27.75 per share after peaking at $29.25 shortly after the opening. Microsoft's two founders, Gates and Allen, were made instant millionaires. Gates owned 45% of the company's 24.7 million outstanding shares and Allen roughly 25%. Gates' stake was therefore $234 million and Microsoft's total-value $520million, at that time.

Post-IPO:
In 1989, Microsoft introduced its flagship office suite, Microsoft Office. The software bundled separate office productivity applications, such as Microsoft Word and Microsoft Excel. On May 22, 1990 Microsoft launched Windows 3.0. The new version of Microsoft's operating system boasted such new features as streamlined user interface graphics and improved protected mode capability for the Intel 386 processor; it sold over 100,000 copies in two weeks. Windows at the time generated more revenue for Microsoft than OS/2, and the company decided to move more resources from OS/2 to Windows. In the ensuing years, the popularity of OS/2 declined, and Windows quickly became the favored PC platform.

During the transition from MS-DOS to Windows, the success of Microsoft's product Microsoft Office allowed the company to gain ground on application-software competitors, such as WordPerfect and Lotus 1-2-3. According to The Register, Novell, an owner of WordPerfect for a time, alleged that Microsoft used its inside knowledge of the DOS and Windows kernels and of undocumented Application Programming Interface features to make Office perform better than its competitors. Eventually, Microsoft Office became the dominant business suite, with a market share far exceeding that of its competitors.
In 1993, Microsoft released Windows NT 3.1, a business operating system with the Windows 3.1 user interface but an entirely different kernel

1995–2005: Internet and legal issues:
In 1995, Microsoft released Windows 95, a new version of the company's flagship operating system which featured a completely new user interface, including a novel start button; more than a million copies of Microsoft Windows 95 were sold in the first four days after its release. The company also released its web browser, Internet Explorer, with the Windows 95 Plus! Pack in August 1995 and subsequent Windows versions.

On, May 26, 1995, following Bill Gates's internal "Internet Tidal Wave memo", Microsoft began to expand its product line into computer networking and the World Wide Web. On August 24, 1995, it launched a major online service, MSN (Microsoft Network), as a direct competitor to AOL. MSN became an umbrella service for Microsoft's online services. The company continued to branch out into new markets in 1996, starting with a joint venture with NBC to create a new 24/7 cable news station, MSNBC. Microsoft entered the personal digital assistant (PDA) market in November with Windows CE 1.0, a new built-from-scratch version of their flagship operating system, specifically designed to run on low-memory, low-performance machines, such as handhelds and other small computers. Later in 1997, Internet Explorer 4.0 was released for both Mac OS and Windows, marking the beginning of the takeover of the browser market from rival Netscape. In October, the Justice Department filed a motion in the Federal District Court in which they stated that Microsoft had violated an agreement signed in 1994, and asked the court to stop the bundling of Internet Explorer with Windows.

The year 1998 was significant in Microsoft's history, with Bill Gates appointing Steve Ballmer as president of Microsoft but remaining as Chair and CEO himself. The company released Windows 98, an update to Windows 95 that incorporated a number of Internet-focused features and support for new types of devices. On April 3, 2000, a judgment was handed down in the case of United States v. Microsoft, calling the company an "abusive monopoly" and forcing the company to split into two separate units. Part of this ruling was later overturned by a federal appeals court, and eventually settled with the U.S. Department of Justice in 2001.2006–present: Vista and other transitions

On June 27, 2008, Bill Gates retired from day-to day activities in the company, following a two year transition period from his role as Chief Software Architect, which was taken by Ray Ozzie, but remained the company's chairman, head of the Board of Directors and would act as an adviser on key projects. Windows Vista, released in January 2007, is Microsoft's latest operating system and has sold 140 million copies to date. Microsoft Office 2007, released at the same time, features a "Ribbon" user interface which is a significant departure from its predecessors. Relatively strong sales of both titles helped to produce a record profit in 2007.

On February 1, 2008, Microsoft made an unsolicited bid to purchase internet services competitor Yahoo! for up to $44.6 billion, though this offer was rejected on February 10. On May 3, 2008, Microsoft withdrew their offer.

Microsoft announced on February 21, 2008 that it will share information about its products and technology to make it easier for developers to create software that works with its products. However, the European Union continued to demonstrate its dissatisfaction with the company for its lack of compliance with the March 2004 judgment and subsequently, on February 27, 2008 imposed a fine of €899 million ($1.4 billion), the largest fine in the history of EU competition policy.

In its January 2009 report of financial results, Microsoft announced layoffs of up to 5,000 employees in response to slowing economic activity due to the ongoing financial crisis.

On February 12, 2009, Microsoft announced its intent to open a small chain of Microsoft-branded retail stores. David Porter, a former executive at Wal-Mart and DreamWorks, was named corporate vice president of Retail Stores
In 2001, Microsoft released Windows XP, the first version that encompassed the features of both its business and home product lines. Before XP was released, Microsoft had to maintain both the NT and the 9x codebase. XP introduced a new graphical user interface, the first such change since Windows 95. In late 2001, with the release of the Xbox, Microsoft entered the multi-billion-dollar game console market dominated by Sony and Nintendo. Microsoft encountered turmoil in March 2004 when antitrust legal action was brought against it by the European Union for abusing its current dominance with the Windows operating system (see European Union Microsoft antitrust case), eventually resulting in a judgment to produce new versions of its Windows XP platform—called Windows XP Home Edition N and Windows XP Professional N—that did not include its Windows Media Player, as well as a fine of €497 million ($613 million).

Product divisions:

To be more precise in tracking performance of each unit and delegating responsibility, Microsoft reorganized into seven core business groups—each an independent financial entity—in April 2002. Later, on September 20, 2005, Microsoft announced a rationalization of its original seven business groups into the three core divisions that exist today: the Windows Client, MSN and Server and Tool groups were merged into the Microsoft Platform Products and Services Division; the Information Worker and Microsoft Business Solutions groups were merged into the Microsoft Business Division; and the Mobile and Embedded Devices and Home and Entertainment groups were merged into the Microsoft Entertainment and Devices Division.

Platform Products and Services Division:
This division produces Microsoft's flagship product, the Windows operating system. It has been produced in many versions, including Windows 3.1, Windows 95, Windows 98, Windows 2000, Windows Me, Windows Server 2003, Windows XP and Windows Vista. Almost all IBM compatible personal computers come with Windows preinstalled. The current desktop version of Windows is Windows Vista. The online service MSN, the cable television station MSNBC and the Microsoft online magazine Slate are all part of this division. (Slate was acquired by The Washington Post on December 21, 2004.) At the end of 1997, Microsoft acquired Hotmail, the most popular webmail service, which it rebranded as "MSN Hotmail". In 1999, Microsoft introduced MSN Messenger, an instant messaging client, to compete with the popular AOL Instant Messenger. Along with Windows Vista, MSN Messenger became Windows Live Messenger.

Microsoft Visual Studio is the company's set of programming tools and compilers. The software product is GUI-oriented and links easily with the Windows APIs, but must be specially configured if used with non-Microsoft libraries. The current version is Visual Studio 2008. The previous version, Visual Studio 2005 was a major improvement over its predecessor, Visual Studio.Net 2003, named after the .NET initiative, a Microsoft marketing initiative covering a number of technologies. Microsoft's definition of .NET continues to evolve. As of 2004, .NET aims to ease the development of Microsoft Windows-based applications that use the Internet, by deploying a new Microsoft communications system, Indigo (now renamed Windows Communication Foundation). This is intended to address some issues previously introduced by Microsoft's DLL design, which made it difficult, even impossible in some situations, to manage, install multiple versions of complex software packages on the same system (see DLL-hell), and provide a more consistent development platform for all Windows applications (see Common Language Infrastructure). In addition, the Company established a set of certification programs to recognize individuals who have expertise in its software and solutions. Similar to offerings from Cisco, Sun Microsystems, Novell, IBM, and Oracle Corporation, these tests are designed to identify a minimal set of proficiencies in a specific role; this includes developers ("Microsoft Certified Solution Developer"), system/network analysts ("Microsoft Certified Systems Engineer"), trainers ("Microsoft Certified Trainers") and administrators ("Microsoft Certified Systems Administrator" and "Microsoft Certified Database Administrator").

Microsoft offers a suite of server software, entitled Windows Server System. Windows Server 2003, an operating system for network servers, is the core of the Windows Server System line. Another server product, Systems Management Server, is a collection of tools providing remote-control abilities, patch management, software distribution and a hardware/software inventory. Other server products include:

* Microsoft SQL Server, a relational database management system;
* Microsoft Exchange Server, for certain business-oriented e-mail and scheduling features;
* Small Business Server, for messaging and other small business-oriented features; and
* Microsoft BizTalk Server, for business process management

Business Division:
The Microsoft Business Division produces Microsoft Office, which is the company's line of office software. The software product includes Word (a word processor), Access (a personal relational database application), Excel (a spreadsheet program), Outlook (Windows-only groupware, frequently used with Exchange Server), PowerPoint (presentation software), and Publisher (desktop publishing software). A number of other products were added later with the release of Office 2003 including Visio, Project, MapPoint, InfoPath and OneNote.

The division also develops financial and business management software for companies. These products include products formerly produced by the Business Solutions Group, which was created in April 2001 with the acquisition of Great Plains. Subsequently, Navision was acquired to provide a similar entry into the European market, resulting in the planned release of Microsoft Dynamics NAV in 2006. The group markets Axapta and Solomon, catering to similar markets, which is scheduled to be combined with the Navision and Great Plains lines into a common platform called Microsoft Dynamics.

Entertainment and Devices Division:
Microsoft has attempted to expand the Windows brand into many other markets, with products such as Windows CE for PDAs and its "Windows-powered" Smartphone products. Microsoft initially entered the mobile market through Windows CE for handheld devices, which today has developed into Windows Mobile 6. The focus of the operating system is on devices where the OS may not directly be visible to the end user, in particular, appliances and cars.

The company produces MSN TV, formerly WebTV, a television-based Internet appliance. Microsoft used to sell a set-top Digital Video Recorder (DVR) called the UltimateTV, which allowed users to record up to 35 hours of television programming from a direct-to-home satellite television provider DirecTV. This was the main competition in the UK for British Sky Broadcasting's (BSkyB) SKY + service, owned by Rupert Murdoch. UltimateTV has since been discontinued, with DirecTV instead opting to market DVRs from TiVo Inc. before later switching to their own DVR brand.

Microsoft sells computer games that run on Windows PCs, including titles such as Age of Empires, Halo and the Microsoft Flight Simulator series. It produces a line of reference works that include encyclopedias and atlases, under the name Encarta. Microsoft Zone hosts free premium and retail games where players can compete against each other and in tournaments.

Microsoft entered the multi-billion-dollar game console market dominated by Sony and Nintendo in late 2001, with the release of the Xbox. The company develops and publishes its own video games for this console, with the help of its Microsoft Game Studios subsidiary, in addition to third-party Xbox video game publishers such as Electronic Arts and Activision, who pay a license fee to publish games for the system. The Xbox also has a successor in the Xbox 360, released on November 22, 2005 in North America and other countries. With the Xbox 360, Microsoft hopes to compensate for the losses incurred with the original Xbox. However, Microsoft made some decisions considered controversial in the video gaming community, such as releasing the console with high failure rates, selling two different versions of the system, one without the hard disk drive and providing limited backward compatibility with only particular Xbox titles.

In addition to the Xbox line of products, Microsoft also markets a number of other computing-related hardware products as well, including mice, keyboards, joysticks, and gamepads, along with other game controllers, the production of which is outsourced in most cases. As of November 15, 2007, Microsoft announced the purchase of Musiwave, Openwave's mobile phone music sales business.

One of Bill Gates' key visions for the company was to "to get a workstation running our software onto every desk and eventually in every home". Because of their huge market share in home and business operating systems, they play an important role in the economics of software.

Microsoft has footholds in other markets besides operating systems and office suites, with assets such as the MSNBC cable television network, the MSN Internet portal, and the Microsoft Encarta multimedia encyclopedia. The company also markets both computer hardware products such as the Microsoft mouse and home entertainment products such as the Xbox, Xbox 360, Zune and MSN TV

User culture:
Technical reference for developers and articles for various Microsoft magazines such as Microsoft Systems Journal (or MSJ) are available through the Microsoft Developer Network, often called MSDN. MSDN also offers subscriptions for companies and individuals, and the more expensive subscriptions usually offer access to pre-release beta versions of Microsoft software. In recent years, Microsoft launched a community site for developers and users, entitled Channel9, which provides many modern features such as a wiki and an Internet forum. Another community site that provides daily videocasts and other services, On10.net, launched on March 3, 2006.

Most free technical support available through Microsoft is provided through online Usenet newsgroups (in the early days it was also provided on CompuServe). There are several of these newsgroups for nearly every product Microsoft provides, and often they are monitored by Microsoft employees. People who are helpful on the newsgroups can be elected by other peers or Microsoft employees for Microsoft Most Valuable Professional (MVP) status, which entitles people to a sort of special social status, in addition to possibilities for awards and other benefits

Corporate affairs:
Corporate structure:
The company is run by a Board of Directors consisting of ten people, made up of mostly company outsiders (as is customary for publicly traded companies). Current members of the board of directors are: Steve Ballmer, James Cash, Jr., Dina Dublon, Bill Gates, Raymond Gilmartin, Reed Hastings, David Marquardt, Charles Noski, Helmut Panke, and Jon Shirley. The ten board members are elected every year at the annual shareholders' meeting, and those who do not get a majority of votes must submit a resignation to the board, which will subsequently choose whether or not to accept the resignation. There are five committees within the board which oversee more specific matters. These committees include the Audit Committee, which handles accounting issues with the company including auditing and reporting; the Compensation Committee, which approves compensation for the CEO and other employees of the company; the Finance Committee, which handles financial matters such as proposing mergers and acquisitions; the Governance and Nominating Committee, which handles various corporate matters including nomination of the board; and the Antitrust Compliance Committee, which attempts to prevent company practices from violating antitrust laws.

There are several other aspects to the corporate structure of Microsoft. For worldwide matters there is the Executive Team, made up of sixteen company officers across the globe, which is charged with various duties including making sure employees understand Microsoft's culture of business. The sixteen officers of the Executive Team include the Chairman and Chief Software Architect, the CEO, the General Counsel and Secretary, the CFO, senior and group vice presidents from the business units, the CEO of the Europe, the Middle East and Africa regions; and the heads of Worldwide Sales, Marketing and Services; Human Resources; and Corporate Marketing. In addition to the Executive Team there is also the Corporate Staff Council, which handles all major staff functions of the company, including approving corporate policies. The Corporate Staff Council is made up of employees from the Law and Corporate Affairs, Finance, Human Resources, Corporate Marketing, and Advanced Strategy and Policy groups at Microsoft. Other Executive Officers include the Presidents and Vice Presidents of the various product divisions, leaders of the marketing section, and the CTO, among others.

Stock:
When the company debuted its IPO in March 13, 1986, the stock price was US $21. By the close of the first trading day, the stock had closed at $28, equivalent to 9.7 cents when adjusted for the company's first nine splits. The initial close and ensuing rise in subsequent years made several Microsoft employees millions. The stock price peaked in 1999 at around US $119 (US $60.928 adjusting for splits).While the company has had nine stock splits, the first of which was in September 18, 1987, the company did not start offering a dividend until January 16, 2003.The dividend for the 2003 fiscal year was eight cents per share, followed by a dividend of sixteen cents per share the subsequent year. The company switched from yearly to quarterly dividends in 2005, for eight cents a share per quarter with a special one-time payout of three dollars per share for the second quarter of the fiscal year.

Despite the company's ninth split on February 2, 2003 and subsequent increases in dividend payouts, the price of Microsoft's stock largely remained steady for the next several years, with a rise in stock price around the release of Windows Vista and a fall during the economic crisis of 2008.

Diversity:
In 2005, Microsoft received a 100% rating in the Corporate Equality Index from the Human Rights Campaign, a ranking of companies by how progressive the organization deems their policies concerning LGBT (lesbian, gay, bisexual and transsexual) employees. Partly through the work of the Gay and Lesbian Employees at Microsoft (GLEAM) group, Microsoft added gender expression to its anti-discrimination policies in April 2005, and the Human Rights Campaign upgraded Microsoft's Corporate Equality Index from its 86% rating in 2004 to its current 100% rating.

In April 2005, Microsoft received wide criticism for withdrawing support from Washington state's H.B. 1515 bill that would have extended the state's current anti-discrimination laws to people with alternate sexual orientations. Microsoft was accused of bowing to pressure from local evangelical pastor Ken Hutcherson who met with a senior Microsoft executive and threatened a national boycott of Microsoft's products. Microsoft also revealed they were paying evangelical conservative Ralph Reed's company Century Strategies a $20,000 monthly fee. Over 2,000 employees signed a petition asking Microsoft to reinstate support for the bill. Under harsh criticism from both outside and inside the company's walls, Microsoft decided to support the bill again in May 2005.

Microsoft hires many foreign workers as well as domestic ones, and is an outspoken opponent of the cap on H1B visas, which allow companies in the United States to employ certain foreign workers. Bill Gates claims the cap on H1B visas make it difficult to hire employees for the company, stating "I'd certainly get rid of the H1B cap."

Logos and slogans:
In 1987, Microsoft adopted its current logo, the so-called "Pac-Man Logo", designed by Scott Baker. According to the March 1987 Computer Reseller News Magazine, "The new logo, in Helvetica italic typeface, has a slash between the o and s to emphasize the "soft" part of the name and convey motion and speed." Dave Norris, a Microsoft employee, ran an internal joke campaign to save the old logo, which was green, in all uppercase, and featured a fanciful letter O, nicknamed the blibbet, but it was discarded.

Microsoft's logo with the "Your potential. Our passion." tagline below the main corporate name, is based on the slogan Microsoft had as of 2008. In 2002, the company started using the logo in the United States and eventually started a TV campaign with the slogan, changed from the previous tagline of "Where do you want to go today?.

Environmental record:
Microsoft is ranked the 2nd worst company for the environment of the 18 rated in Greenpeace's Greener Electronics guide. It received a score of 2.2/10, ahead only of Nintendo.

Microsoft has taken actions to become more environmentally friendly. Some examples include:

* Microsoft's newest building on its campus in Hyderabad, India was built as an environmentally friendly structure. Experts at Microsoft Research India developed a project called Digital Green in 2008, which aims to educate farmers in India on how to use azolla - an aquatic fern fed to cows, yielding increased milk production.

* Microsoft has phased out the use of polyvinyl chloride plastic in its packaging material, due to environmental concerns. Polyvinyl chloride, also referred to as PVC or vinyl, can release toxins into the environment during production and if it is burned after production. These toxins are synthetic chemicals that can be linked to cancer, and issues with the reproductive and immune systems. In six months time, Microsoft was able to eliminate approximately 361,000 pounds of polyvinyl packaging by transitioning to a packaging utilizing polyethylene terephthalate plastic (PET). The company continues to research further eco-friendly packaging made of corn starch, sugar, and vegetable oil.
* Microsoft is using some renewable energy sources in its Silicon Valley campus, where the company has installed over 2,000 solar panels spanning 30,000 square feet (2,800 m2) on top of its buildings. These panels supply 480 kilowatts of power, generating approximately 15 percent of the total energy needed by the campus and cutting the greenhouse gasses that would otherwise be produced to supply that power.
* Microsoft encourages employees to use alternative transporTation options. It created one of the worlds largest private bus systems (the "Connector") as mass transit system in the Seattle area. Employees, interns, vendors and contractors are encouraged to use regional public mass transit with subsidised fares. For on-campus transportation, the "Shuttle Connect" uses a large fleet of hybrid cars, saving over 20,000 galons of fuel per year.
* The company uses an irrigation system at its Redmond campus that senses upcoming weather changes, saving 11 million gallons of water per year.[98] The company has received a silver certification from the U.S. Green Building Council's LEED program for environmental design.
* Beginning in June 2008, Microsoft has added compost bins in all cafeterias on its Redmond campus, and replaced all polystyrene plates and cups and plastic flatware with biodegradable alternatives. In the first two months after this transition, the Redmond campus reduced its non-compost trash output by 50%.

Criticism:
Anti-competitive:
Since the 1980s, Microsoft has been the focus of much controversy in the computer industry. The majority of criticism has been for its business tactics, often described with the motto "embrace, extend and extinguish". Microsoft initially embraces a competing standard or product, then extends it to produce their own version which is then incompatible with the standard, which in time extinguishes competition that does not or cannot use Microsoft's new version. These and other tactics have resulted in lawsuits brought by companies and governments, and billions of dollars in rulings against Microsoft.In January 2009, Opera Software ASA filed a complaint to the European Commission stating that Microsoft's inclusion of Internet Explorer with Windows-based personal computers is a violation of European competition laws.

Freedom and privacy:
Free software proponents point to the company's joining of the Trusted Computing Platform Alliance (TCPA) as a cause of concern. A group of companies that seek to implement an initiative called Trusted Computing (which is claimed to set out to increase security and privacy in a user's computer), the TCPA is decried by critics as a means to allow software developers to enforce any sort of restriction they wish over how their customers use the software they purchased.

“ Large media corporations (including the movie companies and record companies), together with computer companies such as Microsoft and Intel, are planning to make your computer obey them instead of you.”

Advocates of free software also take issue with Microsoft's promotion of Digital Rights Management (DRM) and total cost of ownership (TCO) comparisons with its "Get the facts" campaign. Digital Rights Management is a technology that allows content providers to impose restrictions on the methods by which their products are used on consumer hardware; and subsequently, detractors contend that such technology may infringe on fair use and other rights, especially given that it restricts legal activities such as re-mixing or reproduction of material for use in slide shows or the resale of the goods by the customer.

Misrepresentation:
The "Get the facts" campaign argues that Windows Server has a lower TCO than Linux and lists a variety of studies in order to prove its case. Proponents of Linux unveiled their own study arguing that, contrary to one of Microsoft's claims, Linux has lower management costs than Windows Server.Another study by the Yankee Group claims that upgrading from one version of Windows Server to another costs a significant fraction (a quarter to a third) of the switching costs from Windows Server to Linux, even for large enterprises, and that the other major reasons for a switch away from Windows servers were the increased security and reliability of Linux servers and a chance to escape the Microsoft "lock-in".

In 2004, the Advertising Standards Authority (ASA) of the UK warned Microsoft that an ad from the campaign which claimed that "Linux was ... 10 times more expensive than Windows Server 2003", was "misleading", as the hardware chosen for the Linux server was needlessly expensive.The ASA's complaint was that "the measurements for Linux were performed on an IBM zSeries [mainframe], which was more expensive and did not perform as well as other IBM series." The comparison was to Windows Server 2003 running on two 900 MHz Intel Xeon CPUs.

David Meyer writing on Zdnet.com pointed out that, "Microsoft has a long history of applying for, and being granted patents for, inventions that many argue--and can sometimes demonstrate--were based on earlier work carried out by others, or based on a common, self-evident idea." This was in response to its 2008 patent application for the ability to progress in page-up or page-down increments with a single keystroke — a method that has been pervasive for decades.

References
http://en.wikipedia.org

Windows History - Video

2009-12-25T03:35:00.001-08:00

This video is displaying the Microsoft Windows history.

Re
http://www.youtube.com

Timeline of Linux History

2009-12-12T14:41:00.000-08:00

Timeline of Linux History

1984

January 1984: Richard Stallman quits his job at MIT and starts working on the GNU Project.

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1985

Month unknown: Free Software Foundation, an organization for creating and promoting free software, is founded by Richard Stallman.

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March 1985: The GNU manifesto, a statement by Richard Stallman advocating the cause of free software movement, is published in the March 1985 issue of Dr. Dobb's Journal

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1991

August 25 1991: Linus conceives the idea of Linux and announces the project in a Usenet Post

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September 1991: Version 0.01 is released on the Net

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1992

January 1992: First Linux Newsgroup: alt.os.linux founded in the UseNet

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April 1992: Ari Lemmke starts the popular Linux newsgroup comp.os.linux in the UseNet

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November 1992: Adam Richter announces the release of the first Linux Distribution from his company: Yggdrasil

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1993:

June 1993: Slackware, the famous Linux distribution is released by Peter Volkerding

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August 1993: Matt Welsh releases Linux Installation and getting started: version 1

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1994:

March 1994: Linux kernel version 1.0 is released

Linux

2009-12-12T14:20:00.000-08:00

Linux

Linux (commonly pronounced /ˈlɪnʌks/, LI-nuks in English, also pronounced /ˈlɪnʊks/, LI-nooks) is a generic term referring to Unix-like computer operating systems based on the Linux kernel. Their development is one of the most prominent examples of free and open source software collaboration; typically all the underlying source code can be used, freely modified, and redistributed, both commercially and non-commercially, by anyone under licenses such as the GNU GPL.

Linux is predominantly known for its use in servers, although can be installed on a wide variety of computer hardware, ranging from embedded devices, mobile phones and even some watches to mainframes and supercomputers. Linux distributions, installed on both desktop and laptop computers, have become increasingly commonplace in recent years, partly owing to the popular Ubuntu distribution and the emergence of netbooks.

The name "Linux" comes from the Linux kernel, originally written in 1991 by Linus Torvalds. The rest of the system usually comprises components such as the Apache HTTP Server, the X Window System, the GNOME and KDE desktop environments, and utilities and libraries from the GNU Project (announced in 1983 by Richard Stallman). Commonly-used applications with desktop Linux systems include the Mozilla Firefox web-browser and the OpenOffice.org office application suite. The GNU contribution is the basis for the Free Software Foundation's preferred name GNU/Linux.

History:

Unix:

The Unix operating system was conceived and implemented in 1969 at AT&T's Bell Laboratories in the United States by Ken Thompson, Dennis Ritchie, Douglas McIlroy, and Joe Ossanna. It was first released in 1971 and was initially entirely written in assembly language, a common practice at the time. Later, in a key pioneering approach in 1973, Unix was re-written in the programming language C by Dennis Ritchie, (with exceptions to the kernel and I/O). The availability of an operating system written in a high-level language allowed easier portability to different computer platforms and Unix became widely adopted by academic institutions and businesses. Its design principles were very influential for authors of other systems.

GNU:

The GNU Project, started in 1983 by Richard Stallman, had the goal of creating a "complete Unix-compatible software system" composed entirely of free software. Work began in 1984. Later, in 1985, Stallman created the Free Software Foundation and wrote the GNU General Public License (GNU GPL) in 1989. By the early 1990s, many of the programs required in an operating system (such as libraries, compilers, text editors, a Unix shell, and a windowing system) were completed, although low-level elements such as device drivers, daemons, and the kernel were stalled and incomplete. Linus Torvalds has said that if the GNU kernel had been available at the time (1991), he would not have decided to write his own.

MINIX:

MINIX was an inexpensive minimal Unix-like operating system, designed for education in computer science, written by Andrew S. Tanenbaum (now Minix is free and redesigned also for “serious” use).

In 1991 while attending the University of Helsinki, Torvalds began to work on a non-commercial replacement for MINIX, which would eventually become the Linux kernel.

Torvalds began the development of Linux on Minix and applications written for Minix were also used under Linux. Later Linux matured and it became possible for Linux to be developed under itself. Also GNU applications replaced all Minix ones because, with code from the GNU system freely available, it was advantageous if this could be used with the fledgling OS. Code licensed under the GNU GPL can be used in other projects, so long as they also are released under the same or a compatible license. In order to make the Linux kernel compatible with the components from the GNU Project, Torvalds initiated a switch from his original license (which prohibited commercial redistribution) to the GNU GPL. Developers worked to integrate GNU components with Linux to make a fully functional and free operating system.

Commercial and popular uptake:

Today Linux distributions are used in numerous domains, from embedded systems to supercomputers, and have secured a place in server installations with the popular LAMP application stack. Use of Linux distributions in home and enterprise desktops has been expanding. They have also gained popularity with various local and national governments. The federal government of Brazil is well known for its support for Linux. News of the Russian military creating their own Linux distribution has also surfaced. Indian state of Kerala has gone so far as to make it mandatory for all state high schools to run Linux on their computers.

China uses Linux exclusively as the operating system for its Loongson processor family to achieve technology independence. In Spain some regions have developed their own Linux distributions, which are widely used in education and official institutions, like gnuLinEx in Extremadura and Guadalinex in Andalusia. France and Germany have also taken steps towards the adoption of Linux.

Linux distributions have also become popular with the newly founded netbook market, with many devices such as the ASUS Eee PC and Acer Aspire One shipping with customized Linux distributions pre-installed.

Current development:

Torvalds continues to direct the development of the kernel. Stallman heads the Free Software Foundation, which in turn supports the GNU components. Finally, individuals and corporations develop third-party non-GNU components. These third-party components comprise a vast body of work and may include both kernel modules and user applications and libraries. Linux vendors and communities combine and distribute the kernel, GNU components, and non-GNU components, with additional package management software in the form of Linux distributions.

Design:

A Linux-based system is a modular Unix-like operating system. It derives much of its basic design from principles established in Unix during the 1970s and 1980s. Such a system uses a monolithic kernel, the Linux kernel, which handles process control, networking, and peripheral and file system access. Device drivers are integrated directly with the kernel.

Separate projects that interface with the kernel provide much of the system's higher-level functionality. The GNU userland is an important part of most Linux-based systems, providing the most common implementation of the C library, a popular shell, and many of the common Unix tools which carry out many basic operating system tasks. The graphical user interface (or GUI) used by most Linux systems is based on the X Window System.

User interface:

Users can control a Linux-based system through a command line interface (or CLI), a graphical user interface (or GUI), or through controls attached to the associated hardware (this is common for embedded systems). For desktop systems, the default mode is usually graphical user interface, where the CLI is available through terminal emulator windows or on a separate virtual console.

On desktop machines, KDE, GNOME and Xfce are the most popular user interfaces, though a variety of additional user interfaces exist. Most popular user interfaces run on top of the X Window System (often simply called "X"), which provides network transparency, enabling a graphical application running on one machine to be displayed and controlled from another.

Other GUIs include X window managers such as FVWM, Enlightenment and Window Maker. The window manager provides a means to control the placement and appearance of individual application windows, and interacts with the X Window System. This is a more minimalist goal than KDE, GNOME et al., which are termed desktop environments.

A Linux system typically provides a CLI through a shell, which is the traditional way of interacting with a Unix system. A Linux distribution specialized for servers may use the CLI as its only interface. A headless system that runs without even a monitor can be controlled by the command line via a remote-control protocol such as SSH or telnet.

Most low-level Linux components, including the GNU userland, use the CLI exclusively. The CLI is particularly suited for automation of repetitive or delayed tasks, and provides very simple inter-process communication. A graphical terminal emulator program is often used to access the CLI from a Linux desktop.

Development:

The primary difference between Linux and many other popular contemporary operating systems is that the Linux kernel and other components are free and open source software. Linux is not the only such operating system, although it is by far the most widely used. Some free and open source software licenses are based on the principle of copyleft, a kind of reciprocity: any work derived from a copyleft piece of software must also be copyleft itself. The most common free software license, the GNU GPL, is a form of copyleft, and is used for the Linux kernel and many of the components from the GNU project.

Linux based distributions are intended by developers for interoperability with other operating systems and established computing standards. Linux systems adhere to POSIX, SUS, ISO and ANSI standards where possible, although to date only one Linux distribution has been POSIX.1 certified, Linux-FT.

Free software projects, although developed in a collaborative fashion, are often produced independently of each other. The fact that the software licenses explicitly permit redistribution, however, provides a basis for larger scale projects that collect the software produced by stand-alone projects and make it available all at once in the form of a Linux distribution.

A Linux distribution, commonly called a "distro", is a project that manages a remote collection of system software and application software packages available for download and installation through a network connection. This allows the user to adapt the operating system to his/her specific needs. Distributions are maintained by individuals, loose-knit teams, volunteer organizations, and commercial entities. A distribution can be installed using a CD that contains distribution-specific software for initial system installation and configuration. A package manager such as Synaptic or YAST allows later package upgrades and installations. A distribution is responsible for the default configuration of the installed Linux kernel, general system security, and more generally integration of the different software packages into a coherent whole.

Community:

A distribution is largely driven by its developer and user communities. Some vendors develop and fund their distributions on a volunteer basis, Debian being a well-known example. Others maintain a community version of their commercial distributions, as Red Hat does with Fedora.

In many cities and regions, local associations known as Linux Users Groups (LUGs) seek to promote their preferred distribution and by extension free software. They hold meetings and provide free demonstrations, training, technical support, and operating system installation to new users. Many Internet communities also provide support to Linux users and developers. Most distributions and free software / open source projects have IRC chatrooms or newsgroups. Online forums are another means for support, with notable examples being LinuxQuestions.org and the Gentoo forums. Linux distributions host mailing lists; commonly there will be a specific topic such as usage or development for a given list.

There are several technology websites with a Linux focus. Print magazines on Linux often include cover disks including software or even complete Linux distributions.

Although Linux distributions are generally available without charge, several large corporations sell, support, and contribute to the development of the components of the system and of free software. These include Dell, IBM, HP, Oracle, Sun Microsystems, Novell, Nokia. A number of corporations, notably Red Hat, have built their entire business around Linux distributions.

The free software licenses, on which the various software packages of a distribution built on the Linux kernel are based, explicitly accommodate and encourage commercialization; the relationship between a Linux distribution as a whole and individual vendors may be seen as symbiotic. One common business model of commercial suppliers is charging for support, especially for business users. A number of companies also offer a specialized business version of their distribution, which adds proprietary support packages and tools to administer higher numbers of installations or to simplify administrative tasks. Another business model is to give away the software in order to sell hardware.

Programming on Linux:

Most Linux distributions support dozens of programming languages. The most common collection of utilities for building both Linux applications and operating system programs is found within the GNU toolchain, which includes the GNU Compiler Collection (GCC) and the GNU build system. Amongst others, GCC provides compilers for Ada, C, C++, Java, and Fortran. The Linux kernel itself is written to be compiled with GCC. Proprietary compilers for Linux include the Intel C++ Compiler, Sun Studio, and IBM XL C/C++ Compiler. BASIC is supported in such forms as Gambas, FreeBASIC, and XBasic.

Most distributions also include support for PHP, Perl, Ruby, Python and other dynamic languages. While not as common, Linux also supports C# via the Mono project, sponsored by Novell, and Scheme. A number of Java Virtual Machines and development kits run on Linux, including the original Sun Microsystems JVM (HotSpot), and IBM's J2SE RE, as well as many open-source projects like Kaffe.

The two main frameworks for developing graphical applications are those of GNOME and KDE. These projects are based on the GTK+ and Qt widget toolkits, respectively, which can also be used independently of the larger framework. Both support a wide variety of languages. There are a number of Integrated development environments available including Anjuta, Code::Blocks, Eclipse, KDevelop, Lazarus, MonoDevelop, NetBeans, QtCreator and Omnis Studio while the long-established editors Vim and Emacs remain popular.

Uses:

As well as those designed for general purpose use on desktops and servers, distributions may be specialized for different purposes including: computer architecture support, embedded systems, stability, security, localization to a specific region or language, targeting of specific user groups, support for real-time applications, or commitment to a given desktop environment. Furthermore, some distributions deliberately include only free software. Currently, over three hundred distributions are actively developed, with about a dozen distributions being most popular for general-purpose use.

Linux is a widely ported operating system kernel. The Linux kernel runs on a highly diverse range of computer architectures: in the hand-held ARM-based iPAQ and the mainframe IBM System z9, System z10 in devices ranging from mobile phones to supercomputers. Specialized distributions exist for less mainstream architectures. The ELKS kernel fork can run on Intel 8086 or Intel 80286 16-bit microprocessors, while the µClinux kernel fork may run on systems without a memory management unit. The kernel also runs on architectures that were only ever intended to use a manufacturer-created operating system, such as Macintosh computers (with both PowerPC and Intel processors), PDAs, video game consoles, portable music players, and mobile phones.

There are several industry associations and hardware conferences devoted to maintaining and improving support for diverse hardware under Linux, such as FreedomHEC.

Desktop:

The popularity of Linux on standard desktops (and laptops) has been increasing over the years. Currently most distributions include a graphical user environment. The two most popular such environments, GNOME and KDE, both of which are mature, support a wide variety of languages.

The performance of Linux on the desktop has been a controversial topic; for example in 2007 Con Kolivas accused the Linux community of favoring performance on servers. He quit Linux kernel development because he was frustrated with this lack of focus on the desktop, and then gave a "tell all" interview on the topic. Since then a significant effort has been expended improving the desktop experience. Projects such as upstart aim for a faster boot time. In the field of gaming, the Linux desktop still lags behind Windows. However, there are several companies that do port their own or other companies' games to Linux.

Many types of applications available for Microsoft Windows and Mac OS X are also available for Linux. Commonly, either a free software application will exist which does the functions of an application found on another operating systems, or that application will have a version that works on Linux (such as Skype). Furthermore, the Wine project provides a Windows compatibility layer to run unmodified Windows applications on Linux. CrossOver is a proprietary solution based on the open source Wine project that supports running Windows versions of Microsoft Office, Intuit applications such as Quicken and QuickBooks, Adobe Photoshop versions through CS2, and many popular games such as World of Warcraft and Team Fortress 2. In other cases, there is no Linux port of some software in areas such as desktop publishing and professional audio, there is equivalent software available on Linux.

Many popular applications are available for a wide variety of operating systems. For example Mozilla Firefox, and OpenOffice.org have downloadable versions for all major operating systems. Furthermore, some applications were initially developed for Linux (such as Pidgin, and GIMP) and, due to their popularity, were ported to other operating systems (including Windows and Mac OS X).

A growing number of proprietary desktop applications are also supported on Linux, see List of proprietary software for Linux. In the field of animation and visual effects, most high end software, such as AutoDesk Maya, Softimage XSI and Apple Shake, is available for Linux, Windows and/or Mac OS X.

The collaborative nature of free software development allows distributed teams to localize Linux distributions for use in locales where localizing proprietary systems would not be cost-effective. For example the Sinhalese language version of the Knoppix distribution was available significantly before Microsoft Windows XP was translated to Sinhalese. In this case the Lanka Linux User Group played a major part in developing the localized system by combining the knowledge of university professors, linguists, and local developers.

To install new software in Windows, users either download a digital distribution or use a traditional installation medium (such as CD-ROM). Both of these methods usually provide a "Software Installation Wizard" to guide the user through the setup. On most Linux distributions, there are utilities for browsing a list of thousands of applications installed with a single click. Some of these programs are the Synaptic Package Manager, PackageKit, and Yum Extender. However, installing software not in the official repositories is not always easy, and sometimes the only option is to compile from source.

Servers, mainframes and supercomputers:

Linux distributions have long been used as server operating systems, and have risen to prominence in that area; Netcraft reported in September 2006 that eight of the ten most reliable internet hosting companies ran Linux distributions on their web servers. (As of June 2008, Linux distributions represented five of ten, FreeBSD three of ten, and Microsoft two of ten.)

Linux distributions are the cornerstone of the LAMP server-software combination (Linux, Apache, MySQL, Perl/PHP/Python) which has achieved popularity among developers, and which is one of the more common platforms for website hosting.

Linux distributions have become increasingly popular on mainframes in the last decade due to pricing, compared to other mainframe OS. In December 2009, computer giant IBM reported that it would predominantly market and sell mainframe-based Enterprise Linux Server.

Linux distributions are also commonly used as operating systems for supercomputers: as of June 2009, out of the top 500 systems, 443 (88.6%) run a Linux distribution.

Embedded devices:

Due to its low cost and ability to be easily modified, an embedded Linux is often used in embedded systems. Linux has become a major competitor to the proprietary Symbian OS found in the majority of smartphones—16.7% of smartphones sold worldwide during 2006 were using Linux—and it is an alternative to the proprietary Windows CE and Palm OS operating systems on mobile devices. Cell phones or PDAs running on Linux and built on open source platform became a trend from 2007, like Nokia N810, Openmoko's Neo1973, Motorola RAZR2 v8, Motorola ROKR E8, Motorola MING series, Motorola ZINE and the on-going Google Android. The popular TiVo digital video recorder uses a customized version of Linux. Several network firewall and router standalone products, including several from Cisco/Linksys, use Linux internally, using its advanced firewall and routing capabilities. The Korg OASYS and the Yamaha Motif XS music workstations also run Linux. Furthermore, Linux is used in the leading stage lighting control system, FlyingPig/HighEnd WholeHogIII Console.

Market share and uptake:

Many quantitative studies of free / open source software focus on topics including market share and reliability, with numerous studies specifically examining Linux. The Linux market is growing rapidly, and the revenue of servers, desktops, and packaged software running Linux was expected to exceed $35.7 billion by 2008.

IDC's Q1 2007 report indicated that Linux held 12.7% of the overall server market at that time. This estimate was based on the number of Linux servers sold by various companies and did not include server hardware purchased separately and had Linux installed on it later. In September 2008 Microsoft CEO Steve Ballmer admitted that 60% of web-servers run Linux versus 40% that run Windows Server.

Companies have, mostly based on web server statistics, estimated that the desktop market share of Linux range from less than 1% to 2.14%. Citing methodological problems with those estimates Aaron Seigo of KDE has suggested that it could be 8–12%. In comparison, Microsoft operating systems hold more than 85%.

The frictional cost of switching operating systems and lack of support for certain hardware and application programs designed for Microsoft Windows have been two factors that have inhibited adoption. Proponents and analysts attribute the relative success of Linux to its security, reliability, low cost, and freedom from vendor lock-in.

Also most recently Google has begun to fund Wine, which acts as a compatibility layer, allowing users to run some Windows programs under Linux.

The XO laptop project of One Laptop Per Child is creating a new and potentially much larger Linux community, planned to reach millions of schoolchildren and their families and communities in developing countries. Google, Red Hat, and eBay are major supporters of the project. While the XO will also have a Windows option, it will be primarily deployed using Sugar, a desktop environment for Fedora Linux.

In the film industry, Linux has been the platform of choice for several years. The first major film produced on Linux servers was Titanic in 1997. Since then major studios like Dreamworks Animation, Pixar and Industrial Light & Magic have moved to Linux. Currently more than 95% of the servers and desktops at large animation and visual effects companies use Linux.

The Linux kernel and most GNU software are licensed under the GNU General Public License (GPL). The GPL requires that anyone who distributes the Linux kernel must make the source code (and any modifications) available to the recipient under the same terms. In 1997, Linus Torvalds stated, “Making Linux GPL'd was definitely the best thing I ever did.” Other key components of a Linux system may use other licenses; many libraries use the GNU Lesser General Public License (LGPL), a more permissive variant of the GPL, and the X Window System uses the MIT License.

Torvalds states that the Linux kernel will not move from version 2 of the GPL to version 3. He specifically dislikes some provisions in the new license which prohibit the use of the software in digital rights management, and it would also be impractical to obtain permission from all the copyright holders, who number in the thousands.

A 2001 study of Red Hat Linux 7.1 found that this distribution contained 30 million source lines of code. Using the Constructive Cost Model, the study estimated that this distribution required about eight thousand man-years of development time. According to the study, if all this software had been developed by conventional proprietary means, it would have cost about $1.34 billion (2009 US dollars) to develop in the United States.

Most of the code (71%) was written in the C programming language, but many other languages were used, including C++, assembly language, Perl, Python, Fortran, and various shell scripting languages. Slightly over half of all lines of code were licensed under the GPL. The Linux kernel itself was 2.4 million lines of code, or 8% of the total.

In a later study, the same analysis was performed for Debian GNU/Linux version 4.0 (etch, released 2007). This distribution contained close to 283 million source lines of code, and the study estimated that it would have cost $7.37 billion (2009 US dollars) to develop by conventional means.

In the United States, the name Linux is a trademark registered to Linus Torvalds. Initially, nobody registered it, but on 15 August 1994, William R. Della Croce, Jr. filed for the trademark Linux, and then demanded royalties from Linux distributors. In 1996, Torvalds and some affected organizations sued him to have the trademark assigned to Torvalds, and in 1997 the case was settled. The licensing of the trademark has since been handled by the Linux Mark Institute. Torvalds has stated that he trademarked the name only to prevent someone else from using it. LMI originally charged a nominal sublicensing fee for use of the Linux name as part of trademarks, but later changed this in favor of offering a free, perpetual worldwide sublicense.

GNU/Linux:

The Free Software Foundation views Linux distributions which use GNU software as GNU variants and they ask that such operating systems be referred to as GNU/Linux or a Linux-based GNU system. The media and common usage, however, refers to this family of operating systems simply as Linux, as do many large Linux distributions (e.g. Ubuntu and SuSE Linux). Some distributions use GNU/Linux (particularly notable is Debian GNU/Linux, on which Ubuntu is based), but the term's use outside of the enthusiast community is limited. The naming issue remains controversial.

Reference:

wikipedia.org

LINUX's History

2009-12-12T14:16:00.000-08:00

LINUX's History

Note: The following text was written by Linus on July 31 1992. It is a

collection of various artifacts from the period in which Linux first

began to take shape.

This is just a sentimental journey into some of the first posts

concerning linux, so you can happily press 'n' now if you actually

thought you'd get anything technical.

From: torvalds@klaava.Helsinki.FI (Linus Benedict Torvalds)

Newsgroups: comp.os.minix

Subject: Gcc-1.40 and a posix-question

Message-ID:

Date: 3 Jul 91 10:00:50 GMT

Hello netlanders,

Due to a project I'm working on (in minix), I'm interested in the posix

standard definition. Could somebody please point me to a (preferably)

machine-readable format of the latest posix rules? Ftp-sites would be

nice.

The project was obviously linux, so by July 3rd I had started to think

about actual user-level things: some of the device drivers were ready,

and the harddisk actually worked. Not too much else.

As an aside for all using gcc on minix - [ deleted ]

Just a success-report on porting gcc-1.40 to minix using the 1.37

version made by Alan W Black & co.

Linus Torvalds torvalds@kruuna.helsinki.fi

PS. Could someone please try to finger me from overseas, as I've

installed a "changing .plan" (made by your's truly), and I'm not certain

it works from outside? It should report a new .plan every time.

So I was clueless - had just learned about named pipes. Sue me. This

part of the post got a lot more response than the actual POSIX query,

but the query did lure out arl from the woodwork, and we mailed around

for a bit, resulting in the Linux subdirectory on nic.funet.fi.

Then, almost two months later, I actually had something working: I

made sources for version 0.01 available on nic sometimes around this

time. 0.01 sources weren't actually runnable: they were just a token

gesture to arl who had probably started to despair about ever getting

anything. This next post must have been from just a couple of weeks

before that release.

From: torvalds@klaava.Helsinki.FI (Linus Benedict Torvalds)

Newsgroups: comp.os.minix

Subject: What would you like to see most in minix?

Summary: small poll for my new operating system

Message-ID:

Date: 25 Aug 91 20:57:08 GMT

Organization: University of Helsinki

Hello everybody out there using minix -

I'm doing a (free) operating system (just a hobby, won't be big and

professional like gnu) for 386(486) AT clones. This has been brewing

since april, and is starting to get ready. I'd like any feedback on

things people like/dislike in minix, as my OS resembles it somewhat

(same physical layout of the file-system (due to practical reasons)

among other things).

I've currently ported bash(1.08) and gcc(1.40), and things seem to work.

This implies that I'll get something practical within a few months, and

I'd like to know what features most people would want. Any suggestions

are welcome, but I won't promise I'll implement them :-)

Linus (torvalds@kruuna.helsinki.fi)

PS. Yes - it's free of any minix code, and it has a multi-threaded fs.

It is NOT protable (uses 386 task switching etc), and it probably never

will support anything other than AT-harddisks, as that's all I have :-(.

Judging from the post, 0.01 wasn't actually out yet, but it's close.

I'd guess the first version went out in the middle of September -91. I

got some responses to this (most by mail, which I haven't saved), and

I even got a few mails asking to be beta-testers for linux. After that

just a few general answers to quesions on the net:

From: torvalds@klaava.Helsinki.FI (Linus Benedict Torvalds)

Newsgroups: comp.os.minix

Subject: Re: What would you like to see most in minix?

Summary: yes - it's nonportable

Message-ID:

Date: 26 Aug 91 11:06:02 GMT

Organization: University of Helsinki

In article jkp@cs.HUT.FI (Jyrki Kuoppala) writes:

>> [re: my post about my new OS]

>Tell us more! Does it need a MMU?

Yes, it needs a MMU (sorry everybody), and it specifically needs a

386/486 MMU (see later).

>>PS. Yes - it's free of any minix code, and it has a multi-threaded fs.

>>It is NOT protable (uses 386 task switching etc)

>How much of it is in C? What difficulties will there be in porting?

>Nobody will believe you about non-portability ;-), and I for one would

>like to port it to my Amiga (Mach needs a MMU and Minix is not free).

Simply, I'd say that porting is impossible. It's mostly in C, but most

people wouldn't call what I write C. It uses every conceivable feature

of the 386 I could find, as it was also a project to teach me about the

386. As already mentioned, it uses a MMU, for both paging (not to disk

yet) and segmentation. It's the segmentation that makes it REALLY 386

dependent (every task has a 64Mb segment for code & data - max 64 tasks

in 4Gb. Anybody who needs more than 64Mb/task - tough cookies).

It also uses every feature of gcc I could find, specifically the __asm__

directive, so that I wouldn't need so much assembly language objects.

Some of my "C"-files (specifically mm.c) are almost as much assembler as

C. It would be "interesting" even to port it to another compiler (though

why anybody would want to use anything other than gcc is a mystery).

Note: linux has in fact gotten more portable with newer versions:

there was a lot more assembly in the early versions. It has in fact

been ported to other architectures by now.

Unlike minix, I also happen to LIKE interrupts, so interrupts are

handled without trying to hide the reason behind them (I especially like

my hard-disk-driver. Anybody else make interrupts drive a state-

machine?). All in all it's a porters nightmare.

>As for the features; well, pseudo ttys, BSD sockets, user-mode

>filesystems (so I can say cat /dev/tcp/kruuna.helsinki.fi/finger),

>window size in the tty structure, system calls capable of supporting

>POSIX.1. Oh, and bsd-style long file names.

Most of these seem possible (the tty structure already has stubs for

window size), except maybe for the user-mode filesystems. As to POSIX,

I'd be delighted to have it, but posix wants money for their papers, so

that's not currently an option. In any case these are things that won't

be supported for some time yet (first I'll make it a simple minix-

lookalike, keyword SIMPLE).

Linus (torvalds@kruuna.helsinki.fi)

PS. To make things really clear - yes I can run gcc on it, and bash, and

most of the gnu [bin/file]utilities, but it's not very debugged, and the

library is really minimal. It doesn't even support floppy-disks yet. It

won't be ready for distribution for a couple of months. Even then it

probably won't be able to do much more than minix, and much less in some

respects. It will be free though (probably under gnu-license or similar).

Well, obviously something worked on my machine: I doubt I had yet

gotten gcc to compile itself under linux (or I would have been too

proud of it not to mention it). Still before any release-date.

Then, October 5th, I seem to have released 0.02. As I already

mentioned, 0.01 didn't actually come with any binaries: it was just

source code for people interested in what linux looked like. Note the

lack of announcement for 0.01: I wasn't too proud of it, so I think I

only sent a note to everybody who had shown interest.

From: torvalds@klaava.Helsinki.FI (Linus Benedict Torvalds)

Newsgroups: comp.os.minix

Subject: Free minix-like kernel sources for 386-AT

Message-ID:

Date: 5 Oct 91 05:41:06 GMT

Organization: University of Helsinki

Do you pine for the nice days of minix-1.1, when men were men and wrote

their own device drivers? Are you without a nice project and just dying

to cut your teeth on a OS you can try to modify for your needs? Are you

finding it frustrating when everything works on minix? No more all-

nighters to get a nifty program working? Then this post might be just

for you :-)

As I mentioned a month(?) ago, I'm working on a free version of a

minix-lookalike for AT-386 computers. It has finally reached the stage

where it's even usable (though may not be depending on what you want),

and I am willing to put out the sources for wider distribution. It is

just version 0.02 (+1 (very small) patch already), but I've successfully

run bash/gcc/gnu-make/gnu-sed/compress etc under it.

Sources for this pet project of mine can be found at nic.funet.fi

(128.214.6.100) in the directory /pub/OS/Linux. The directory also

contains some README-file and a couple of binaries to work under linux

(bash, update and gcc, what more can you ask for :-). Full kernel

source is provided, as no minix code has been used. Library sources are

only partially free, so that cannot be distributed currently. The

system is able to compile "as-is" and has been known to work. Heh.

Sources to the binaries (bash and gcc) can be found at the same place in

/pub/gnu.

ALERT! WARNING! NOTE! These sources still need minix-386 to be compiled

(and gcc-1.40, possibly 1.37.1, haven't tested), and you need minix to

set it up if you want to run it, so it is not yet a standalone system

for those of you without minix. I'm working on it. You also need to be

something of a hacker to set it up (?), so for those hoping for an

alternative to minix-386, please ignore me. It is currently meant for

hackers interested in operating systems and 386's with access to minix.

The system needs an AT-compatible harddisk (IDE is fine) and EGA/VGA. If

you are still interested, please ftp the README/RELNOTES, and/or mail me

for additional info.

I can (well, almost) hear you asking yourselves "why?". Hurd will be

out in a year (or two, or next month, who knows), and I've already got

minix. This is a program for hackers by a hacker. I've enjouyed doing

it, and somebody might enjoy looking at it and even modifying it for

their own needs. It is still small enough to understand, use and

modify, and I'm looking forward to any comments you might have.

I'm also interested in hearing from anybody who has written any of the

utilities/library functions for minix. If your efforts are freely

distributable (under copyright or even public domain), I'd like to hear

from you, so I can add them to the system. I'm using Earl Chews estdio

right now (thanks for a nice and working system Earl), and similar works

will be very wellcome. Your (C)'s will of course be left intact. Drop me

a line if you are willing to let me use your code.

Linus

PS. to PHIL NELSON! I'm unable to get through to you, and keep getting

"forward error - strawberry unknown domain" or something.

Well, it doesn't sound like much of a system, does it? It did work,

and some people even tried it out. There were several bad bugs (and

there was no floppy-driver, no VM, no nothing), and 0.02 wasn't really

very useable.

0.03 got released shortly thereafter (max 2-3 weeks was the time

between releases even back then), and 0.03 was pretty useable. The

next version was numbered 0.10, as things actually started to work

pretty well. The next post gives some idea of what had happened in two

months more...

From: torvalds@klaava.Helsinki.FI (Linus Benedict Torvalds)

Newsgroups: comp.os.minix

Subject: Re: Status of LINUX?

Summary: Still in beta

Message-ID:

Date: 19 Dec 91 23:35:45 GMT

Organization: University of Helsinki

In article miquels@maestro.htsa.aha.nl (Miquel van Smoorenburg) writes:

>Hello *,

> I know some people are working on a FREE O/S for the 386/486,

>under the name Linux. I checked nic.funet.fi now and then, to see what was

>happening. However, for the time being I am without FTP access so I don't

>know what is going on at the moment. Could someone please inform me about it

>It's maybe best to follow up to this article, as I think that there are

>a lot of potential interested people reading this group. Note, that I don't

>really *have* a >= 386, but I'm sure in time I will.

Linux is still in beta (although available for brave souls by ftp), and

has reached the version 0.11. It's still not as comprehensive as

386-minix, but better in some respects. The "Linux info-sheet" should

be posted here some day by the person that keeps that up to date. In

the meantime, I'll give some small pointers.

First the bad news:

- Still no SCSI: people are working on that, but no date yet.

Thus you need a AT-interface disk (I have one report that it

works on an EISA 486 with a SCSI disk that emulates the

AT-interface, but that's more of a fluke than anything else:

ISA+AT-disk is currently the hardware setup)

As you can see, 0.11 had already a small following. It wasn't much,

but it did work.

- still no init/login: you get into bash as root upon bootup.

That was still standard in the next release.

- although I have a somewhat working VM (paging to disk), it's not

ready yet. Thus linux needs at least 4M to be able to run the

GNU binaries (especially gcc). It boots up in 2M, but you

cannot compile.

I actually released a 0.11+VM version just before Christmas -91: I

didn't need it myself, but people were trying to compile the kernel in

2MB and failing, so I had to implement it. The 0.11+VM version was

available only to a small number of people that wanted to test it out:

I'm still surprised it worked as well as it did.

- minix still has a lot more users: better support.

- it hasn't got years of testing by thousands of people, so there

are probably quite a few bugs yet.

Then for the good things..

- It's free (copyright by me, but freely distributable under a

very lenient copyright)

The early copyright was in fact much more restrictive than the GNU

copyleft: I didn't allow any money at all to change hands due to

linux. That changed with 0.12.

- it's fun to hack on.

- /real/ multithreading filesystem.

- uses the 386-features. Thus locked into the 386/486 family, but

it makes things clearer when you don't have to cater to other

chips.

- a lot more... read my .plan.

/I/ think it's better than minix, but I'm a bit prejudiced. It will

never be the kind of professional OS that Hurd will be (in the next

century or so :), but it's a nice learning tool (even more so than

minix, IMHO), and it was/is fun working on it.

Linus (torvalds@kruuna.helsinki.fi)

---- my .plan --------------------------

Free UNIX for the 386 - coming 4QR 91 or 1QR 92.

The current version of linux is 0.11 - it has most things a unix kernel

needs, and will probably be released as 1.0 as soon as it gets a little

more testing, and we can get a init/login going. Currently you get

dumped into a shell as root upon bootup.

Linux can be gotten by anonymous ftp from 'nic.funet.fi' (128.214.6.100)

in the directory '/pub/OS/Linux'. The same directory also contains some

binary files to run under Linux. Currently gcc, bash, update, uemacs,

tar, make and fileutils. Several people have gotten a running system,

but it's still a hackers kernel.

Linux still requires a AT-compatible disk to be useful: people are

working on a SCSI-driver, but I don't know when it will be ready.

There are now a couple of other sites containing linux, as people have

had difficulties with connecting to nic. The sites are:

Tupac-Amaru.Informatik.RWTH-Aachen.DE (137.226.112.31):

directory /pub/msdos/replace

tsx-11.mit.edu (18.172.1.2):

directory /pub/linux

There is also a mailing list set up 'Linux-activists@niksula.hut.fi'.

To join, mail a request to 'Linux-activists-request@niksula.hut.fi'.

It's no use mailing me: I have no actual contact with the mailing-list

(other than being on it, naturally).

Mail me for more info:

Linus (torvalds@kruuna.Helsinki.FI)

0.11 has these new things:

- demand loading

- code/data sharing between unrelated processes

- much better floppy drivers (they actually work mostly)

- bug-corrections

- support for Hercules/MDA/CGA/EGA/VGA

- the console also beeps (WoW! Wonder-kernel :-)

- mkfs/fsck/fdisk

- US/German/French/Finnish keyboards

- settable line-speeds for com1/2

As you can see: 0.11 was actually stand-alone: I wrote the first

mkfs/fsck/fdisk programs for it, so that you didn't need minix any

more to set it up. Also, serial lines had been hard-coded to 2400bps,

as that was all I had.

Still lacking:

- init/login

- rename system call

- named pipes

- symbolic links

Well, they are all there now: init/login didn't quite make it to 0.12,

and rename() was implemented as a patch somewhere between 0.12 and

0.95. Symlinks were in 0.95, but named pipes didn't make it until

0.96.

Note: The version number went directly from 0.12 to 0.95, as the

follow-on to 0.12 was getting feature-full enough to deserve a number

in the 0.90's

0.12 will probably be out in January (15th or so), and will have:

- POSIX job control (by tytso)

- VM (paging to disk)

- Minor corrections

Actually, 0.12 was out January 5th, and contained major corrections.

It was in fact a very stable kernel: it worked on a lot of new

hardware, and there was no need for patches for a long time. 0.12 was

also the kernel that "made it": that's when linux started to spread a

lot faster. Earlier kernel releases were very much only for hackers:

0.12 actually worked quite well.

Note: The following document is a reply by Linus Torvalds, creator of

Linux, in which he talks about his experiences in the early stages of

Linux development

To: Linux-Activists@BLOOM-PICAYUNE.MIT.EDU

From: torvalds@klaava.Helsinki.FI (Linus Benedict Torvalds)

Subject: Re: Writing an OS - questions !!

Date: 5 May 92 07:58:17 GMT

In article nani@td2cad.intel.com (V. Narayanan) writes:

Hi folks,

For quite some time this "novice" has been wondering as to how one goe

about the task of writing an OS from "scratch". So here are some questions,

and I would appreciate if you could take time to answer 'em.

Well, I see someone else already answered, but I thought I'd take on the

linux-specific parts. Just my personal experiences, and I don't know

how normal those are.

1) How would you typically debug the kernel during the development phase?

Depends on both the machine and how far you have gotten on the kernel:

on more simple systems it's generally easier to set up. Here's what I

had to do on a 386 in protected mode.

The worst part is starting off: after you have even a minimal system you

can use printf etc, but moving to protected mode on a 386 isn't fun,

especially if you at first don't know the architecture very well. It's

distressingly easy to reboot the system at this stage: if the 386

notices something is wrong, it shuts down and reboots - you don't even

get a chance to see what's wrong.

Printf() isn't very useful - a reboot also clears the screen, and

anyway, you have to have access to video-mem, which might fail if your

segments are incorrect etc. Don't even think about debuggers: no

debugger I know of can follow a 386 into protected mode. A 386 emulator

might do the job, or some heavy hardware, but that isn't usually

feasible.

What I used was a simple killing-loop: I put in statements like

die:

jmp die

at strategic places. If it locked up, you were ok, if it rebooted, you

knew at least it happened before the die-loop. Alternatively, you might

use the sound io ports for some sound-clues, but as I had no experience

with PC hardware, I didn't even use that. I'm not saying this is the

only way: I didn't start off to write a kernel, I just wanted to explore

the 386 task-switching primitives etc, and that's how I started off (in

about April-91).

After you have a minimal system up and can use the screen for output, it

gets a bit easier, but that's when you have to enable interrupts. Bang,

instant reboot, and back to the old way. All in all, it took about 2

months for me to get all the 386 things pretty well sorted out so that I

no longer had to count on avoiding rebooting at once, and having the

basic things set up (paging, timer-interrupt and a simple task-switcher

to test out the segments etc).

2) Can you test the kernel functionality by running it as a process on a

different OS? Wouldn't the OS(the development environment) generate

exceptions in cases when the kernel (of the new OS) tries to modify

'priviledged' registers?

Yes, it's generally possible for some things, but eg device drivers

usually have to be tested out on the bare machine. I used minix to

develop linux, so I had no access to IO registers, interrupts etc.

Under DOS it would have been possible to get access to all these, but

then you don't have 32-bit mode. Intel isn't that great - it would

probably have been much easier on a 68040 or similar.

So after getting a simple task-switcher (it switched between two

processes that printed AAAA... and BBBB... respectively by using the

timer-interrupt - Gods I was proud over that), I still had to continue

debugging basically by using printf. The first thing written was the

keyboard driver: that's the reason it's still written completely in

assembler (I didn't dare move to C yet - I was still debugging at

about instruction-level).

After that I wrote the serial drivers, and voila, I had a simple

terminal program running (well, not that simple actually). It was still

the same two processes (AAA..), but now they read and wrote to the

console/serial lines instead. I had to reboot to get out of it all, but

it was a simple kernel.

After that is was plain sailing: hairy coding still, but I had some

devices, and debugging was easier. I started using C at this stage, and

it certainly speeds up developement. This is also when I start to get

serious about my megalomaniac ideas to make "a better minix that minix".

I was hoping I'd be able to recompile gcc under linux some day...

The harddisk driver was more of the same: this time the problems with

bad documentation started to crop up. The PC may be the most used

architecture in the world right now, but that doesn't mean the docs are

any better: in fact I haven't seen /any/ book even mentioning the weird

386-387 coupling in an AT etc (Thanks Bruce).

After that, a small filesystem, and voila, you have a minimal unix. Two

months for basic setups, but then only slightly longer until I had a

disk-driver (seriously buggy, but it happened to work on my machine) and

a small filesystem. That was about when I made 0.01 available (late

august-91? Something like that): it wasn't pretty, it had no floppy

driver, and it couldn't do much anything. I don't think anybody ever

compiled that version. But by then I was hooked, and didn't want to

stop until I could chuck out minix.

3) Would new linkers and loaders have to be written before you get a basic

kernel running?

All versions up to about 0.11 were crosscompiled under minix386 - as

were the user programs. I got bash and gcc eventually working under

0.02, and while a race-condition in the buffer-cache code prevented me

from recompiling gcc with itself, I was able to tackle smaller compiles.

0.03 (October?) was able to recompile gcc under itself, and I think

that's the first version that anybody else actually used. Still no

floppies, but most of the basic things worked.

Afetr 0.03 I decided that the next version was actually useable (it was,

kind of, but boy is X under 0.96 more impressive), and I called the next

version 0.10 (November?). It still had a rather serious bug in the

buffer-cache handling code, but after patching that, it was pretty ok.

0.11 (December) had the first floppy driver, and was the point where I

started doing linux developement under itself. Quite as well, as I

trashed my minix386 partition by mistake when trying to autodial

/dev/hd2.

By that time others were actually using linux, and running out of

memory. Especially sad was the fact that gcc wouldn't work on a 2MB

machine, and although c386 was ported, it didn't do everything gcc did,

and couldn't recompile the kernel. So I had to implement disk-paging:

0.12 came out in January (?) and had paging by me as well as job control

by tytso (and other patches: pmacdona had started on VC's etc). It was

the first release that started to have "non-essential" features, and

being partly written by others. It was also the first release that

actually did many things better than minix, and by now people started to

really get interested.

Then it was 0.95 in March, bugfixes in April, and soon 0.96. It's

certainly been fun (and I trust will continue to be so) - reactions have

been mostly very positive, and you do learn a lot doing this type of

thing (on the other hand, your studies suffer in other respects :)

Linus

History of Mac OS

2009-12-12T00:18:00.000-08:00

History of Mac OS

On January 24, 1984, Apple Computer Inc. (now Apple Inc.) introduced the Macintosh personal computer, with the Macintosh 128K model, which came bundled with the Mac OS operating system, then known as the System Software.[1] The Macintosh is often credited with

popularizing the graphical user interface. The Mac OS has been pre-installed o

almost every Macintosh computer ever sold. The operating system is also sold separately at Apple retail stores, and online. The original Mac OS was partially based on the Lisa OS, previously released by Apple for the Lisa computer in 1983 and, as part of an agreement allowing Xerox to buy shares in Apple at a favorable rate, it also used concepts from the Xerox PARC Xerox Alto, which Steve Jobs and several other Macintosh team members had previewed.

Early history:

Development:

The Macintosh project started in early 1979 with Jef Raskin, who envisioned an easy-to-use, low-cost computer for the average consumer. In September 1979, Raskin was given permission to start hiring for the project and was, in particular, looking for an engineer that could put together a prototype. Bill Atkinson, a member of the Apple Lisa team, introduced him to Burrell Smith, a service technician who had been hired earlier that year.[citation needed]

In January 1981, Steve Jobs completely took over the Macintosh project.

Jobs and a number of Apple engineers

visited Xerox PARC in December 1979, three months after the Lisa and Macintosh projects had begun. After hearing about the pioneering GUI technology being developed at Xerox PARC from former Xerox employees like Raskin, Jobs negotiated a visit to see the Xerox Alto computer and Smalltalk development tools in exchange for Apple stock options.[2] The final Lisa and Macintosh operating systems mostly used concepts from the Xerox Alto, but many elements of the graphical user interface were created by Apple including the menubar, pop-up menus and the concepts of drag and drop and direct manipulation.[3]

Unlike the IBM PC, which used 8 kB of system ROM for power-on

self-test (POST) and basic input/output system (BIOS), the Mac ROM was significantly larger (64 kB) and held key OS code. Much of the original Mac ROM was coded by Andy Hertzfeld, a member o

f the original Macintosh team. He was able to conserve some of the precious ROM space by interleaving some of the assembly language code. In addition to coding the ROM, he also coded the kernel, the Macintosh Toolbox and some of the desktop accessories (DAs) as well. The icons of the operating system, which represented folders and application software were designed by Susan Kare, who later designed the icons for Microsoft Windows 3.0. Bruce Horn and Steve Capps wrote the Macintosh Finder as well as a number of Macintosh system utilities.

Apple was very strong in advertising their newfound machine. After it was created, the company bought all 39 pages of advertisement space in the Newsweek magazine, 1984 November/December edition. Apple was so successful in its marketing for the Macintosh, that it quickly outshone its more sophisticated

predecessor, the Lisa, in sales – so much so that Apple quickly developed a product called MacWorks which allowed the Lisa to emulate Macintosh system software through System 3, by which time it had been discontinued as the re-branded Macintosh XL. Many of Lisa's operating system advances would not appear in the operating system until System 7.

[edit]Release

The first version of the Mac OS (simply called System) is easily distinguished between other operating systems from the same period because it does not use a command line interface; it was one of the first operating systems to use an entirely graphical user interface. Additional to the system kernel is the Finder, an application used for file management, which also displays the Desktop. The two files were contained in a folder directory labeled System Folder, which contained other resource files, like a printer driver, needed to interact with the System.

System 1, 2, 3 & 4:

These releases could only run one application at a time, though special application shells such as Switcher (discussed under MultiFinder) could work around this to some extent. System 1.0, 1.1, and 2.0 used a flat file system with only one kludged level of folders, called Macintosh File System (MFS); its support for folders (subdirectories) was incomplete. System 2.0 added support for AppleTalk and the newly introduced LaserWriter to use it. System 2.1 (Finder 5.0) introduced the HFS (Hierarchical File System) which had real directories. This version was

specifically to support the Hard Disk 20 and only implemented HFS in RAM, startup and most floppy disks remained MFS 400K volumes. System 3.0 was introduced with the Mac Plus, officially implementing HFS and 800K startup drives and adding support for several new technologies including SCSI and AppleShare and introducing Trash "bulging" (i.e., when the Trash contained files, it would gain a bulged appearance). System 4.0 came with the Mac SE and Macintosh II, which required additional support for the first expansion slots, the Apple Desktop Bus (ADB), internal hard drives and on the Mac II, color, larger displays and the first Motorola 68020 processor.

System Software 5:

System Software 5 (also referred to as simply System 5) added MultiFinder, an extension which let the system run several programs at once. The system used a co-operative multitasking model, meaning that time was given to the background applications only when the running

application yielded control. A clever change in system functions that applications were already calling to handle events made many existing applications share time automatically. Users could also choose to not use MultiFinder, and thus stick with using a single application at a time as in previous releases of the system software.

System Software 5 was also the first Macintosh operating system to be given a unified "Macintosh System Software" version number, as opposed to the numbers used for the System and Finder files.

System Software 6:

System Software 6 (also referred to simply as System 600) was a consolidation release of the Mac OS, producing a complete, stable, and long-lasting operating system. Two major hardware introductions requiring additional support under System 6 were the 68030 processor and

1.44MB SuperDrive debuting with the Macintosh IIx and Macintosh SE/30. Later it would include support for the first specialized laptop features with the introduction of the Macintosh Portable. From System 6 forward, the Finder would have a unified version number closely matching that of the System.

System 7:

On May 13, 1991 System 7 was released. It was the second major upgrade to the Mac OS, adding a significant user interface overhaul, new applications, stability improvements and many new features. Its introduction coincided with the release of and provided support for the 68040 Macintosh line.

Perhaps the most significant feature of System 7 was page swapping support, which previously had only been available as a third-party add-on. Accompanying this was a move to 32-bit memory addressing, necessary for the ever-increasing amounts of RAM available to the Motorola 68030 CPU. Earlier versions of Mac OS had used the lower 24 bits for addressing, and the upper 8 bits for flags. This had been an effective solution for earlier Macintosh models with very limited amounts of RAM, but it became a liability[12] later. Apple described code that

assumed the 24 + 8-bit addressing as being "not 32-bit clean", and most such applications would crash when 32-bit addressing was enabled by the user. The original Macs used the Motorola 68000 CPU which could address only 16 MB of memory. 24 Bits is all that is needed to address the 16MB memory space. This was a hardware limitation, not a system software design fault. The 68020/68030/68040 CPUs have 32-bit address buses and can address up to 4 GB of physical memory. As Apple moved to the 68030 CPU it needed to allow the use of more than 16 MB of memory. Thus the transition to 32-bit clean ROMs and software had to be implemented.

One notable System 7 feature was the built-in co-operative multitasking. In System Software 6, this function was optional through the MultiFinder. System 7 also introduced aliases, similar to shortcuts that were introduced in later versions of Microsoft Windows. System extensions were enhanced, by being moved to their own subfolder; a subfolder in the System Folder was also created for the control panels. In System 7.5, Apple included the Extensions Manager, a previously third-party program which simplified the process of enabling and disabling extensions.

The Apple menu, home only to desk accessories in System 6, was made more general-purpose: the user could now make often-used folders and applications—or anything else they desired—appear in the menu by placing aliases to them in an "Apple Menu Items" subfolder of the System Folder. AppleScript, a scripting language for automating tasks, was also introduced with System 7. 32-bit QuickDraw, supporting so-called "true color" imaging, was also included as standard; it was previously available as a system extension. TrueType, an outline font standard, was also introduced with System 7.

The Trash, under System 6 and earlier, would empty itself automatically when shutting down the computer or, if MultiFinder were not running, when launching an application. System 7 reimplemented the Trash as a special hidden folder, allowing files to remain in it across reboots until the user deliberately chose the "Empty Trash" command.

System 7.1 was mainly a bugfix release, with a few minor features added. System 7.1 was not only the first operating system to cost money (all previous versions were free or sold at the cost of the floppies), but also received a "Pro" sibling with extra features. System 7.1.2 was the first version to support PowerPC-based Macs. System 7.1 also introduced the System Enablers as a method to support new models without updating the actual System file. This led to extra files inside the system folder (one per new model supported) that some users found unpleasing.

System 7.5 introduced a large number of "high level" additions, considered by some to be less well thought-out than they could have been.[citation needed] Many of the new features were based on shareware applications that Apple bought and included into the new system. On the newer PowerPC machines, System 7.5 was plagued by stability problems due partly to a new memory manager (which can be turned off), and poor OS handling of errors in PowerPC code (all PowerPC exceptions map to Type 11). These growing pains did not afflict the 68k-architecture machines.

Mac OS 7.6:

Stability improved in PPC Macs with Mac OS 7.6, which dropped the "System" moniker as a more-trademarkable name was needed in order to license the OS to the growing market of third-party Macintosh clone manufacturers. Mac OS 7.6 required a 68030 CPU and 32 bit clean ROMs, and so dropped support for many of the early Macs, including the Mac Plus and Mac II.

Version history:

System 7.0 (integrated MultiFinder always enabled)

System 7.0.1 (introduced with LC II and Quadra series)

System 7 Tuner (update for both 7.0 and 7.0.1)

System 7.1

System 7.1 Pro (version 7.1.1, combined with PowerTalk, Speech Manager & Macintalk, Thread Manager)

System 7.1.2 (first version for Macs equipped with a PowerPC processor)

System 7.1.2P (only for Performa/LC/Quadra 630 series, very quickly replaced by 7.5)

System 7.5

System 7.5.1 (System 7.5 Update 1.0 — the first Macintosh operating system to call itself "Mac OS")

System 7.5.2 (first version for Power Macs that use PCI expansion cards, usable only on these Power Macs and PowerBooks 5300 and Duo 2300)

System 7.5.3 (System 7.5 Update 2.0)

System 7.5.3L (only for Mac clones)

System 7.5.3 Revision 2

System 7.5.3 Revision 2.1 (only for Performa 6400/180 and 6400/200)

System 7.5.4, released very briefly and withdrawn within hours. Replaced by 7.5.5

System 7.5.5 Last to support non-32 bit clean Macs, including all with less than a 68030 CPU.

Mac OS 7.6 (name formally changed because of the experimental clone program, although System 7.5.1 and later used the "Mac OS" name on the splash screen)

Mac OS 7.6.1 Proper PowerPC error handling introduced.

Performas used to have their own, exclusive operating system before they were merged into System 7.5.

System 7.0.1P

System 7.1P

System 7.1P1

System 7.1P2

System 7.1P3 (last release with new features)

System 7.1P4

System 7.1P5

System 7.1P6

Mac OS 8:

Mac OS 8 was released on July 26, 1997, shortly after Steve Jobs returned to the company.

It was mainly released to keep the Mac OS moving forward during a difficult time for Apple.

Initially planned as Mac OS 7.7, it was renumbered "8" to exploit a legal loophole to accomplish Jobs's goal of terminating third-party manufacturers' licenses to System 7 and shutting down the Macintosh clone market.[citation needed] 8.0 added a number of features from the stillborn Copland project, while leaving the underlying operating system unchanged. A multi-threaded

Finder was included, enabling better multi-tasking. The GUI was changed in appearance to a new shaded greyscale look called Platinum, and the ability to change the appearance themes (also known as skins) was added with a new control panel. This capability was provided by a new "appearance" API layer within the OS, one of the few significant changes.

Apple sold 1.2 million copies of Mac OS 8 in its first two weeks of availability and 3 million within six months. In light of Apple's financial difficulties at the time, there was a large grassroots movement among Mac users to upgrade and 'help save Apple'. Even some pirate groups refused to redistribute the OS.[citation needed]

Mac OS 8.1 saw the introduction of an updated version of the Hierarchical File System called HFS Plus, which fixed many of the limitations of the earlier system (HFS Plus continues to be used in Mac OS X). There were some other interface changes such as separating network features from printing (the venerable, and rather odd Chooser was at last headed for retirement), and some improvements to application switching. However, in underlying technical respects, Mac OS 8 was not very different from System 7.

Mac OS 8.5 focused on speed and stability, with lots of old 68k code replaced by modern code native to the PowerPC. It also improved the appearance on the system, although the theming feature was cut late in development.

Mac OS 8.0 (first version to require a 68040 processor, dropping support for the remainder of the Macintosh II series and other 68030 Macs, added support for the PowerPC G3 processor)

Mac OS 8.1 (last version to run on a 68K processor, added support for USB on the Bondi iMac, added support for HFS+)

Mac OS 8.5 (first version to run only on a PowerPC processor, added built-in support for Firewire on the PowerMac G3)

Mac OS 8.5.1

Mac OS 8.6 (included a new nanokernel for improved performance and Multiprocessing Services 2.0 support, added support for the PowerPC G4 processor).

Mac OS 9:

Mac OS 9 was released on October 23, 1999. It was generally a steady evolution from Mac OS 8. Early development releases of Mac OS 9 were numbered 8.7. Mac OS 9 added improved support for AirPort wireless networking. It introduced an early implementation of multi-user support (though not considered a true multi-user operating system by modern standards). An improved Sherlock search engine added several new search plug-ins. Mac OS 9 also provided a much improved memory implementation and management. AppleScript was improved to allow TCP/IP and networking control. Mac OS 9 also made the first use of the centralized Apple Software Update to find and install OS and hardware updates. Other new features included its on-the-fly file encryption software with code signing and Keychain technologies, Remote Networking and File Server packages and much improved list of USB drivers.

Mac OS 9 also added some transitional technologies to help application developers adopt some Mac OS X features before the introduction of the new OS to the public, again easing the transition. These included new APIs for the file system, and the bundling of the Carbon library that apps could link against instead of the traditional API libraries — apps that were adapted to do this can be run natively on Mac OS X as well. Other changes were made in Mac OS 9 to allow it to be booted in the "classic environment" within Mac OS X. This is a compatibility layer in Mac OS X (in fact a Mac OS X application, originally codenamed the "blue box") that runs a complete Mac OS 9 operating system, so allowing applications that have not been ported to Carbon to run on Mac OS X. This is reasonably seamless, though "classic" applications retain their original Mac OS 8/9 appearance and do not gain the Mac OS X "Aqua" appearance.

Mac OS 9.0

Mac OS 9.0.2

Mac OS 9.0.3

Mac OS 9.0.4

Mac OS 9.1

Mac OS 9.2

Mac OS 9.2.1

Mac OS 9.2.2

Mac OS X:

Mac OS X (pronounced /mæk oʊ ɛs tɛn/)[13] is the line of graphical operating systems developed, marketed, and sold by Apple Inc. which succeeded the original Mac OS, which had been Apple's primary operating system since 1984. Unlike the earlier Macintosh operating system, Mac OS X is a Unix-based operating system[14] built on technology developed at NeXT from the second half of the 1980s until early 1997, when Apple purchased the company.[15]

The first version was Mac OS X Server 1.0 in 1999, which retained the earlier Mac operating system's "platinum" appearance and even resembled OPENSTEP in places. The desktop-oriented version, Mac OS X 10.0, followed in March 2001 sporting the new Aqua user interface. Since then, six more distinct "end-user" and "server" versions have been released, most recently Mac OS X 10.6 in August 2009. Releases of Mac OS X are named after big cats. For example, Apple calls Mac OS X 10.5 "Leopard," while its previous release was called "Tiger."

Versions of Mac OS X:

Mac OS X 10.0 (Cheetah)

Mac OS X 10.1 (Puma)

Mac OS X 10.2 (Jaguar)

Mac OS X 10.3 (Panther)

Mac OS X 10.4 (Tiger)

Mac OS X 10.5 (Leopard)

Mac OS X 10.6 (Snow Leopard)

Reference:

wikipedia.org

History of operating systems

2009-12-12T00:03:00.000-08:00

History of operating systems

The history of computer operating systems recapitulates to a degree the recent history of computer hardware.
Operating systems (OSes) provide a set of functions needed and used by most application-programs on a computer, and the necessary linkages for the control and synchronization of the computer's hardware. On the first computers, without an operating system, every program needed the full hardware specification to run correctly and perform standard tasks, and its own drivers for peripheral devices like printers and card-readers. The growing complexity of hardware and application-programs eventually made operating systems a necessity.

Background:
The user had sole use of the machine and would arrive armed with program and data, often on punched paper and tape. The program would be loaded into the machine, and the machine would be set to work until the program completed or crashed. Programs could generally be debugged via a front panel using switches and lights. It is said that Alan Turing was a master of this on the early Manchester Mark 1 machine, and he was already deriving the primitive conception of an operating system from the principles of the Universal Turing machine.
Later machines came with libraries of support code, which would be linked to the user's program to assist in operations such as input and output. This was the genesis of the modern-day operating system. However, machines still ran a single job at a time; at Cambridge University in England the job queue was at one time a washing line from which tapes were hung with different colored clothes-pegs to indicate job-priority.
As machines became more powerful, the time to run programs diminished and the time to hand off the equipment became very large by comparison. Accounting for and paying for machine usage moved on from checking the wall clock to automatic logging by the computer. Run queues evolved from a literal queue of people at the door, to a heap of media on a jobs-waiting table, or batches of punch-cards stacked one on top of the other in the reader, until the machine itself was able to select and sequence which magnetic tape drives were online. Where program developers had originally had access to run their own jobs on the machine, they were supplanted by dedicated machine operators who looked after the well-being and maintenance of the machine and were less and less concerned with implementing tasks manually. When commercially available computer centers were faced with the implications of data lost through tampering or operational errors, equipment vendors were put under pressure to enhance the runtime libraries to prevent misuse of system resources. Automated monitoring was needed not just for CPU usage but for counting pages printed, cards punched, cards read, disk storage used and for signaling when operator intervention was required by jobs such as changing magnetic tapes.
All these features were building up towards the repertoire of a fully capable operating system. Eventually the runtime libraries became an amalgamated program that was started before the first customer job and could read in the customer job, control its execution, clean up after it, record its usage, and immediately go on to process the next job. Significantly, it became possible for programmers to use symbolic program-code instead of having to hand-encode binary images, once task-switching allowed a computer to perform translation of a program into binary form before running it. These resident background programs, capable of managing multistep processes, were often called monitors or monitor-programs before the term OS established itself.
An underlying program offering basic hardware-management, software-scheduling and resource-monitoring may seem a remote ancestor to the user-oriented OSes of the personal computing era. But there has been a shift in meaning. With the era of commercial computing, more and more "secondary" software was bundled in the OS package, leading eventually to the perception of an OS as a complete user-system with utilities, applications (such as text editors and file managers) and configuration tools, and having an integrated graphical user interface. The true descendant of the early operating systems is what is now called the "kernel". In technical and development circles the old restricted sense of an OS persists because of the continued active development of embedded operating systems for all kinds of devices with a data-processing component, from hand-held gadgets up to industrial robots and real-time control-systems, which do not run user-applications at the front-end. An embedded OS in a device today is not so far removed as one might think from its ancestor of the 1950s.
The broader categories of systems and application software are discussed in the computer software article.

The mainframe era:
It is generally thought that the first operating system used for real work was GM-NAA I/O, produced in 1956 by General Motors' Research division for its IBM 704. Most other early operating systems for IBM mainframes were also produced by customers.
Early operating systems were very diverse, with each vendor or customer producing one or more operating systems specific to their particular mainframe computer. Every operating system, even from the same vendor, could have radically different models of commands, operating procedures, and such facilities as debugging aids. Typically, each time the manufacturer brought out a new machine, there would be a new operating system, and most applications would have to be manually adjusted, recompiled, and retested.

Systems on IBM hardware:
Main article: History of IBM mainframe operating systems
The state of affairs continued until the 1960s when IBM, already a leading hardware vendor, stopped the work on existing systems, and put all the effort into developing the System/360 series of machines, all of which used the same instruction architecture. IBM intended to develop also a single operating system for the new hardware, the OS/360. The problems encountered in the development of the OS/360 are legendary, and are described by Fred Brooks in The Mythical Man-Month—a book that has become a classic of software engineering. Because of performance differences across the hardware range and delays with software development, a whole family of operating systems were introduced instead of a single OS/360.
IBM wound up releasing a series of stop-gaps followed by three longer-lived operating systems:
OS/MFT for mid-range systems. This had one successor, OS/VS1, which was discontinued in the 1980s.
OS/MVT for large systems. This was similar in most ways to OS/MFT (programs could be ported between the two without being re-compiled), but has more sophisticated memory management and a time-sharing facility, TSO. MVT had several successors including the current z/OS.
DOS/360 for small System/360 models had several successors including the current z/VSE. It was significantly different from OS/MFT and OS/MVT.
IBM maintained full compatibility with the past, so that programs developed in the sixties can still run under z/VSE (if developed for DOS/360) or z/OS (if developed for OS/MFT or OS/MVT) with no change.

Other mainframe operating systems:
Control Data Corporation developed the SCOPE operating system in the 1960s, for batch processing. In cooperation with the University of Minnesota, the KRONOS and later the NOS operating systems were developed during the 1970s, which supported simultaneous batch and timesharing use. Like many commercial timesharing systems, its interface was an extension of the DTSS time sharing system, one of the pioneering efforts in timesharing and programming languages.
In the late 1970s, Control Data and the University of Illinois developed the PLATO system, which used plasma panel displays and long-distance time sharing networks. PLATO was remarkably innovative for its time; the shared memory model of PLATO's TUTOR programming language allowed applications such as real-time chat and multi-user graphical games.
UNIVAC, the first commercial computer manufacturer, produced a series of EXEC operating systems. Like all early main-frame systems, this was a batch-oriented system that managed magnetic drums, disks, card readers and line printers. In the 1970s, UNIVAC produced the Real-Time Basic (RTB) system to support large-scale time sharing, also patterned after the Dartmouth BASIC system.
Burroughs Corporation introduced the B5000 in 1961 with the MCP (Master Control Program) operating system. The B5000 was a stack machine designed to exclusively support high-level languages with no machine language or assembler and indeed the MCP was the first OS to be written exclusively in a high-level language (ESPOL, a dialect of ALGOL). MCP also introduced many other ground-breaking innovations, such as being the first commercial implementation of virtual memory. MCP is still in use today in the Unisys ClearPath/MCP line of computers.
Project MAC at MIT, working with GE, developed Multics and General Electric Comprehensive Operating Supervisor (GECOS), which introduced the concept of ringed security privilege levels. After Honeywell acquired GE's computer business, it was renamed to General Comprehensive Operating System (GCOS).
Digital Equipment Corporation developed many operating systems for its various computer lines, including TOPS-10 and TOPS-20 time sharing systems for the 36-bit PDP-10 class systems. Prior to the widespread use of UNIX, TOPS-10 was a particularly popular system in universities, and in the early ARPANET community.
In the late 1960s through the late 1970s, several hardware capabilities evolved that allowed similar or ported software to run on more than one system. Early systems had utilized microprogramming to implement features on their systems in order to permit different underlying architecture to appear to be the same as others in a series. In fact most 360's after the 360/40 (except the 360/165 and 360/168) were microprogrammed implementations. But soon other means of achieving application compatibility were proven to be more significant.

Minicomputers and the rise of UNIX:
The beginnings of the UNIX operating system was developed at AT&T Bell Laboratories in the late 1960s. Because it was essentially free in early editions, easily obtainable, and easily modified, it achieved wide acceptance. It also became a requirement within the Bell systems operating companies. Since it was written in a high level C language, when that language was ported to a new machine architecture UNIX was also able to be ported. This portability permitted it to become the choice for a second generation of minicomputers and the first generation of workstations. By widespread use it exemplified the idea of an operating system that was conceptually the same across various hardware platforms. It still was owned by AT&T and that limited its use to groups or corporations who could afford to license it. It became one of the roots of the open source movement.
Other than that Digital Equipment Corporation created the simple RT-11 system for its 16-bit PDP-11 class machines, and the VMS system for the 32-bit VAX computer.
Another system which evolved in this time frame was the Pick operating system. The Pick system was developed and sold by Microdata Corporation who created the precursors of the system. The system is an example of a system which started as a database application support program and graduated to system work.

The case of 8-bit home computers and game consoles:
Home computers:
Although most small 8-bit home computers of the 1980s, such as the Commodore 64, the Atari 8-bit, the Amstrad CPC, ZX Spectrum series and others could use a disk-loading operating system, such as CP/M or GEOS they could generally work without one. In fact, most if not all of these computers shipped with a built-in BASIC interpreter on ROM, which also served as a crude operating system, allowing minimal file management operations (such as deletion, copying, etc.) to be performed and sometimes disk formatting, along of course with application loading and execution, which sometimes required a non-trivial command sequence, like with the Commodore 64.
The fact that the majority of these machines were bought for entertainment and educational purposes and were seldom used for more "serious" or business/science oriented applications, partly explains why a "true" operating system was not necessary.
Another reason is that they were usually single-task and single-user machines and shipped with minimal amounts of RAM, usually between 4 and 256 kilobytes, with 64 and 128 being common figures, and 8-bit processors, so an operating system's overhead would likely compromise the performance of the machine without really being necessary.
Even the available word processor and integrated software applications were mostly self-contained programs which took over the machine completely, as also did video games.

Game consoles and video games:
Since virtually all video game consoles and arcade cabinets designed and built after 1980 were true digital machines (unlike the analog Pong clones and derivatives), some of them carried a minimal form of BIOS or built-in game, such as the ColecoVision, the Sega Master System and the SNK Neo Geo. There were however successful designs where a BIOS was not necessary, such as the Nintendo NES and its clones.
Modern day game consoles and videogames, starting with the PC-Engine, all have a minimal BIOS that also provides some interactive utilities such as memory card management, Audio or Video CD playback, copy protection and sometimes carry libraries for developers to use etc. Few of these cases, however, would qualify as a "true" operating system.
The most notable exceptions are probably the Dreamcast game console which includes a minimal BIOS, like the PlayStation, but can load the Windows CE operating system from the game disk allowing easily porting of games from the PC world, and the Xbox game console, which is little more than a disguised Intel-based PC running a secret, modified version of Microsoft Windows in the background. Furthermore, there are Linux versions that will run on a Dreamcast and later game consoles as well.
Long before that, Sony had released a kind of development kit called the Net Yaroze for its first PlayStation platform, which provided a series of programming and developing tools to be used with a normal PC and a specially modified "Black PlayStation" that could be interfaced with a PC and download programs from it. These operations require in general a functional OS on both platforms involved.
In general, it can be said that videogame consoles and arcade coin operated machines used at most a built-in BIOS during the 1970s, 1980s and most of the 1990s, while from the PlayStation era and beyond they started getting more and more sophisticated, to the point of requiring a generic or custom-built OS for aiding in development and expandability.

The personal computer era: Apple, Amiga, PC/MS/DR-DOS and beyond:
The development of microprocessors made inexpensive computing available for the small business and hobbyist, which in turn led to the widespread use of interchangeable hardware components using a common interconnection (such as the S-100, SS-50, Apple II, ISA, and PCI buses), and an increasing need for 'standard' operating systems to control them. The most important of the early OSes on these machines was Digital Research's CP/M-80 for the 8080 / 8085 / Z-80 CPUs. It was based on several Digital Equipment Corporation operating systems, mostly for the PDP-11 architecture. Microsoft's first Operating System, M-DOS, was designed along many of the PDP-11 features, but for microprocessor based system. MS-DOS (or PC-DOS when supplied by IBM) was based originally on CP/M-80. Each of these machines had a small boot program in ROM which loaded the OS itself from disk. The BIOS on the IBM-PC class machines was an extension of this idea and has accreted more features and functions in the 20 years since the first IBM-PC was introduced in 1981.
The decreasing cost of display equipment and processors made it practical to provide graphical user interfaces for many operating systems, such as the generic X Window System that is provided with many UNIX systems, or other graphical systems such as Microsoft Windows, the RadioShack Color Computer's OS-9 Level II/MultiVue, Commodore's AmigaOS, Apple's Mac OS, or even IBM's OS/2. The original GUI was developed at Xerox Palo Alto Research Center in the early '70s (the Alto computer system) and imitated by many vendors.

The rise of virtualization:
Operating systems were originally running directly on the hardware itself, and provided services to applications. With VM/CMS on System/370, IBM introduced the notion of virtual machine, where the operating system itself runs under the control of a hypervisor, instead of being in direct control of the hardware. VMware popularized this technology on personal computers. Over time, the line between virtual machines monitors and operating systems was blurred:
Hypervisors grew more complex, gaining their own application programming interface, memory management or file system
Virtualization becomes a key feature of operating systems, as exemplified by Hyper-V in Windows Server 2008 or HP Integrity Virtual Machines in HP-UX
In some systems, such as POWER5 and POWER6-based servers from IBM, the hypervisor is no longer optional
Applications have been re-designed to run directly on a virtual machine monitor
In many ways, virtual machine software today plays the role formerly held by the operating system, including managing the hardware resources (processor, memory, I/O devices), applying scheduling policies, or allowing system administrators to manage the system.