COMPUTER SYSTEMS

welcome,,,

2011-06-20T00:00:00.001-07:00

welcome to my blog viewers,,,,

HACKING TIPS

2011-05-21T21:35:00.000-07:00

Access Free Airtel GPRS Using TeaShark Browser

TeaShark, a mobile browser like Opera Mini, allow you to access Airtel GPRS for FREE.
Shockingly it has nothing to do with modifying any Airtel settings or any kind of hack.

Here is how I used this…

* Download TeaShark v. 312. Its free and being JAR file it can be installed on most handsets.
* Open it from your mobile and select AirTel Live as access point.
* That’s it! Open any site from TeaShark and you won’t be charged anything.

Note for the first time, when TeaShark starts, it may take more than one minute to initialize. Also this one time initialization may fail many times. But don’t loose your heart!

As of now, this trick is limited to handsets only.

Note : “Subscribe to Packet Data First”
This means you need to activate AirTel Live service which is free.
Contact customer care to get it activated.
Also select only AirTel Live as access point when prompted by TeaShark.

Parallel ATA

2011-05-17T10:04:00.000-07:00

Parallel ATA

From Wikipedia, the free encyclopedia

**Parallel ATA**
Production history
ATA connector on the right, with two motherboard ATA sockets on the left.
Type	Internal storage device connector
Designer	Western Digital, subsequently amended by many others
Designed	1986
Superseded by	Serial ATA (2003)
General specifications
Hot pluggable	No
External	No
Cable	40 or 80 wires ribbon cable
Pins	40
Data
Width	16 bits
Bitrate	16 MB/s originally later 33, 66, 100 and 133 MB/s
Max. devices	2 (master/slave)
Protocol	Parallel
Pin out

Pin 1		Reset
Pin 2		Ground
Pin 3		Data 7
Pin 4		Data 8
Pin 5		Data 6
Pin 6		Data 9
Pin 7		Data 5
Pin 8		Data 10
Pin 9		Data 4
Pin 10		Data 11
Pin 11		Data 3
Pin 12		Data 12
Pin 13		Data 2
Pin 14		Data 13
Pin 15		Data 1
Pin 16		Data 14
Pin 17		Data 0
Pin 18		Data 15
Pin 19		Ground
Pin 20		Key or VCC_in
Pin 21		DDRQ
Pin 22		Ground
Pin 23		I/O write
Pin 24		Ground
Pin 25		I/O read
Pin 26		Ground
Pin 27		IOCHRDY
Pin 28		Cable select
Pin 29		DDACK
Pin 30		Ground
Pin 31		IRQ
Pin 32		No connect
Pin 33		Addr 1
Pin 34		GPIO_DMA66_Detect
Pin 35		Addr 0
Pin 36		Addr 2
Pin 37		Chip select 1P
Pin 38		Chip select 3P
Pin 39		Activity
Pin 40		Ground

Parallel ATA (PATA), originally ATA, is an interface standard for the connection of storage devices such as hard disks, solid-state drives, floppy drives, and optical disc drives in computers. The standard is maintained by X3/INCITS committee.^[1] It uses the underlying AT Attachment (ATA) and AT Attachment Packet Interface (ATAPI) standards.
The Parallel ATA standard is the result of a long history of incremental technical development, which began with the original AT Attachment interface, developed for use in early PC AT equipment. The ATA interface itself evolved in several stages from Western Digital's original Integrated Drive Electronics (IDE) interface. As a result, many near-synonyms for ATA/ATAPI and its previous incarnations are still in common informal use. After the introduction of Serial ATA in 2003, the original ATA was retroactively renamed Parallel ATA.
Parallel ATA cables have a maximum allowable length of only 18 in (457 mm). Because of this limit, the technology normally appears as an internal computer storage interface. For many years ATA provided the most common and the least expensive interface for this application. It has largely been replaced by Serial ATA (SATA) in newer systems.

1 History and terminology
- 1.1 IDE and ATA-1
- 1.2 Second ATA interface
- 1.3 EIDE and ATA-2
- 1.4 ATAPI
- 1.5 UDMA and ATA-4
- 1.6 Current terminology
- 1.7 Drive size limitations
- 1.8 Obsolescence
2 Parallel ATA interface
3 ATA standards versions, transfer rates, and features
- 3.1 Features introduced with each ATA revision
- 3.2 Speed of defined transfer modes
4 Related standards, features, and proposals
- 4.1 ATAPI Removable Media Device (ARMD)
- 4.2 ATA over Ethernet
5 See also
6 References

History and terminology

The standard was originally conceived as "PC/AT Attachment" as its primary feature was a direct connection to the 16-bit ISA bus introduced with the IBM PC/AT. The "AT" in "IBM PC/AT" is an initialism for "Advanced Technology," but that term does not appear in current or recent versions of the ATA specification; it is simply "AT Attachment". This name was chosen to avoid possible trademark issues.

IDE and ATA-1

The first version of what is now called the ATA/ATAPI interface was developed by Western Digital under the name Integrated Drive Electronics (IDE). Together with Control Data Corporation (who manufactured the hard drive part) and Compaq Computer (into whose systems these drives would initially go), they developed the connector, the signaling protocols, and so on with the goal of remaining software compatible with the existing ST-506 hard drive interface.^[2] The first such drives appeared in Compaq PCs in 1986.^[3]^[4]
The term Integrated Drive Electronics refers not just to the connector and interface definition, but also to the fact that the drive controller is integrated into the drive, as opposed to a separate controller on or connected to the motherboard. The interface cards used to connect a parallel ATA drive to, for example, a PCI slot are not drive controllers, they are merely bridges between the host bus and the ATA interface. Since the original ATA interface is essentially just a 16-bit ISA slot in disguise, the bridge was especially simple in case of an ATA connector being located on an ISA interface card. The integrated controller presented the drive to the host computer as an array of 512-byte blocks with a relatively simple command interface. This relieved the mainboard and interface cards in the host computer of the chores of stepping the disk head arm, moving the head arm in and out, and so on, as had to be done with earlier ST-506 and ESDI hard drives. All of these low-level details of the mechanical operation of the drive were now handled by the controller on the drive itself. This also eliminated the need to design a single controller that could handle many different types of drives, since the controller could be unique for the drive. The host need only ask for a particular sector, or block, to be read or written, and either accept the data from the drive or send the data to it.
The interface used by these drives was standardized in 1994 as ANSI standard X3.221-1994, AT Attachment Interface for Disk Drives. After later versions of the standard were developed, this became known as "ATA-1".^[5]^[6]
A short-lived, seldom-used implementation of ATA was created for the IBM XT and similar machines that used the 8-bit version of the ISA bus. It has been referred to as "XTA" or "XT Attachment."^[7]

Second ATA interface

When PC motherboard makers started to include onboard ATA interfaces in place of the earlier ISA plug-in cards, there was usually only one ATA connector on the board, which could support up to two hard drives. At the time in combination with the floppy drive, this was sufficient for most people, and eventually it became common to have two hard drives installed. When the CD-ROM was developed, many computers would have been unable to accept these drives if they had been ATA devices, due to already having two hard drives installed. Adding the CD-ROM drive would have required removal of one of the drives.
SCSI was available as a CD-ROM expansion option at the time, but devices with SCSI were more expensive than ATA devices due to the need for a smart interface that is capable of bus arbitration. SCSI typically added US$ 100-300 to the cost of a storage device, in addition to the cost of a SCSI host adapter.
The less-expensive solution was the addition of a dedicated CD-ROM interface, typically included as an expansion option on a sound card. It was included on the sound card because early business PCs did not include support for more than simple beeps from the internal speaker, and tuneful sound playback was considered unnecessary for early business software. When the CD-ROM was introduced, it was logical to also add digital audio to the computer at the same time (for the same reason, sound cards tended to include a gameport interface for joysticks). An older business PC could be upgraded in this manner to meet the Multimedia PC standard for early software packages that used sound (which required the sound card) and colorful video animation (which required the CD-ROM as floppy disks simply did not have the necessary data capacity).
The second drive interface initially was not well-defined. It was first introduced with interfaces specific to certain CD-ROM drives such as Mitsumi, Sony or Panasonic drives,^[8] and it was common to find early sound cards with two or three separate connectors each designed to match a certain brand of CD-ROM drive. This evolved into the standard ATA interface for ease of cross-compatibility, though the sound card ATA interface still usually supported only a single CD-ROM and not hard drives.
This second ATA interface on the sound card eventually evolved into the second motherboard ATA interface which was long included as a standard component in all PCs. Called the "primary" and "secondary" ATA interfaces, they were assigned to base addresses 0x1F0 and 0x170 on ISA bus systems.

EIDE and ATA-2

In 1994, about the same time that the ATA-1 standard was adopted, Western Digital introduced drives under a newer name, Enhanced IDE (EIDE). These included most of the features of the forthcoming ATA-2 specification and several additional enhancements. Other manufacturers introduced their own variations of ATA-1 such as "Fast ATA" and "Fast ATA-2".
The new version of the ANSI standard, AT Attachment Interface with Extensions ATA-2 (X3.279-1996), was approved in 1996. It included most of the features of the manufacturer-specific variants.^[9]^[10]
ATA-2 also was the first to note that devices other than hard drives could be attached to the interface:

3.1.7 Device: Device is a storage peripheral. Traditionally, a device on the ATA interface has been a hard disk drive, but any form of storage device may be placed on the ATA interface provided it adheres to this standard.
—from,^[10] page 2

ATAPI

As mentioned in the previous sections, ATA was originally designed for, and worked only with hard disks and devices that could emulate them. The introduction of ATAPI (ATA Packet Interface) by a group called the Small Form Factor committee allowed ATA to be used for a variety of other devices that require functions beyond those necessary for hard disks. For example, any removable media device needs a "media eject" command, and a way for the host to determine whether the media is present, and these were not provided in the ATA protocol.
The Small Form Factor committee approached this problem by defining ATAPI, the "ATA Packet Interface". ATAPI is actually a protocol allowing the ATA interface to carry SCSI commands and responses; therefore all ATAPI devices are actually "speaking SCSI" other than at the electrical interface. In fact, some early ATAPI devices were simply SCSI devices with an ATA/ATAPI to SCSI protocol converter added on. The SCSI commands and responses are embedded in "packets" (hence "ATA Packet Interface") for transmission on the ATA cable. This allows any device class for which a SCSI command set has been defined to be interfaced via ATA/ATAPI.
ATAPI devices are also "speaking ATA", as the ATA physical interface and protocol are still being used to send the packets. On the other hand, ATA hard drives and solid state drives do not use ATAPI.
ATAPI devices include CD-ROM and DVD-ROM drives, tape drives, and large-capacity floppy drives such as the Zip drive and SuperDisk drive.
The SCSI commands and responses used by each class of ATAPI device (CD-ROM, tape, etc.) are described in other documents or specifications specific to those device classes and are not within ATA/ATAPI or the T13 committee's purview.
ATAPI was adopted as part of ATA in INCITS 317-1998, AT Attachment with Packet Interface Extension (ATA/ATAPI-4).^[11]^[12]^[13]

UDMA and ATA-4

The ATA/ATAPI-4 also introduced several "Ultra DMA" transfer modes. These initially supported speeds from 16 MByte/s to 33 MByte/second. In later versions faster Ultra DMA modes were added, requiring a new 80-wire cable to reduce crosstalk. The latest versions of Parallel ATA support up to 133 MByte/s.

Current terminology

The terms "integrated drive electronics" (IDE), "enhanced IDE" and "EIDE" have come to be used interchangeably with ATA (now Parallel ATA, or PATA).
In addition there have been several generations of "EIDE" drives marketed, compliant with various versions of the ATA specification. An early "EIDE" drive might be compatible with ATA-2, while a later one with ATA-6.
Nevertheless a request for an "IDE" or "EIDE" drive from a computer parts vendor will almost always yield a drive that will work with most Parallel ATA interfaces.
Another common usage is to refer to the specification version by the fastest mode supported. For example, ATA-4 supported Ultra DMA modes 0 through 2, the latter providing a maximum transfer rate of 33 megabytes per second. ATA-4 drives are thus sometimes called "UDMA-33" drives, and sometimes "ATA-33" drives. Similarly, ATA-6 introduced a maximum transfer speed of 100 megabytes per second, and some drives complying to this version of the standard are marketed as "PATA/100" drives.

Drive size limitations

See also: Enhanced BIOS

The original ATA specification used a 28-bit addressing mode, allowing for the addressing of 2²⁸ (268,435,456) sectors (blocks) of 512 bytes each, resulting in a maximum capacity of 128 GiB (137 GB).^[14] The BIOS in early PCs imposed smaller limits such as 8.46 GB, with a maximum of 1024 cylinders, 256 heads and 63 sectors, but this was not a limit imposed by the ATA interface.
ATA-6 introduced 48-bit addressing, increasing the limit to 128 PiB (144 PB). As a consequence, any ATA drive of capacity larger than about 137 gigabytes must be an ATA-6 or later drive. Connecting such a drive to a host with an ATA-5 or earlier interface will limit the usable capacity to the maximum of the interface.
Some operating systems, including Windows XP pre-SP 1, and Windows 2000, disable 48-bit LBA by default, requiring the user to take extra steps to use the entire capacity of an ATA drive larger than about 137 gigabytes.^[15] Older operating systems, such as Windows 98, do not support 48-bit LBA at all.

Obsolescence

For a long period of time, ATA ruled as the primary storage device interface and in some systems a third and fourth motherboard interface was provided (for example, Promise Ultra-100), for up to eight ATA devices attached to the motherboard.
After the introduction of SATA (Serial ATA), use of Parallel ATA declined, and new motherboards had only a single PATA connector, for up to two PATA optical drives, along with (typically) six or more SATA connectors for hard drives and other devices. In new computers, the parallel ATA interface is rarely used, and several PC chipsets have removed support for PATA, and motherboard vendors still wishing to offer ATA with those chipsets must include an additional interface chip.

Parallel ATA interface

Parallel ATA cables transfer data 16 bits at a time. The traditional cable uses 40-pin connectors attached to a ribbon cable. Each cable has two or three connectors, one of which plugs into an adapter interfacing with the rest of the computer system. The remaining connector(s) plug into drives.
ATA's cables have had 40 wires for most of its history (44 conductors for the smaller form-factor version used for 2.5" drives — the extra four for power), but an 80-wire version appeared with the introduction of the Ultra DMA/33 (UDMA) mode. All of the additional wires in the new cable are ground wires, interleaved with the previously defined wires to reduce the effects of capacitive coupling between neighboring signal wires, reducing crosstalk. Capacitive coupling is more of a problem at higher transfer rates, and this change was necessary to enable the 66 megabytes per second (MB/s) transfer rate of UDMA4 to work reliably. The faster UDMA5 and UDMA6 modes also require 80-conductor cables.

ATA cables:
40 wire ribbon cable (top)
80 wire ribbon cable (bottom)

Though the number of wires doubled, the number of connector pins and the pinout remain the same as 40-conductor cables, and the external appearance of the connectors is identical. Internally the connectors are different; the connectors for the 80-wire cable connect a larger number of ground wires to a smaller number of ground pins, while the connectors for the 40-wire cable connect ground wires to ground pins one-for-one. 80-wire cables usually come with three differently colored connectors (blue, black, and gray for controller, master drive, and slave drive respectively) as opposed to uniformly colored 40-wire cable's connectors (commonly all gray). The gray connector on 80-conductor cables has pin 28 CSEL not connected, making it the slave position for drives configured cable select.
Round parallel ATA cables (as opposed to ribbon cables) were eventually made available as they were believed to have less effect on computer cooling and were easier to handle; however, only ribbon cables are supported by the ATA specifications.

Pin 20

In the ATA standard pin 20 is defined as (mechanical) key and is not used. This socket on the female connector is often obstructed, requiring pin 20 to be omitted from the male cable or drive connector, making it impossible to plug it in the wrong way round; a male connector with pin 20 present cannot be used. However, some flash memory drives can use pin 20 as VCC_in to power the drive without requiring a special power cable; this feature can only be used if the equipment supports this use of pin 20.^[16]

Pin 28

Pin 28 of the gray (slave/middle) connector of an 80 conductor cable is not attached to any conductor of the cable. It is attached normally on the black (master drive end) and blue (motherboard end) connectors.

Pin 34

Pin 34 is connected to ground inside the blue connector of an 80 conductor cable but not attached to any conductor of the cable. It is attached normally on the gray and black connectors. See page 315 of.^[17]

Differences between connectors on 80-conductor cables

The image shows PATA connectors after removal of strain relief, cover, and cable. Pin one is at bottom left of the connectors, pin 2 is top left, etc., except that the lower image of the blue connector shows the view from the opposite side, and pin one is at top right.
Each contact comprises a pair of points which together pierce the insulation of the ribbon cable with such precision that they make a connection to the desired conductor without harming the insulation on the neighboring wires. The center row of contacts are all connected to the common ground bus and attached to the odd numbered conductors of the cable. The top row of contacts are the even-numbered sockets of the connector (mating with the even-numbered pins of the receptacle) and attach to every other even-numbered conductor of the cable. The bottom row of contacts are the odd-numbered sockets of the connector (mating with the odd-numbered pins of the receptacle) and attach to the remaining even-numbered conductors of the cable.
Note the connections to the common ground bus from sockets 2 (top left), 19 (center bottom row), 22, 24, 26, 30, and 40 on all connectors. Also note (enlarged detail, bottom, looking from the opposite side of the connector) that socket 34 of the blue connector does not contact any conductor but unlike socket 34 of the other two connectors, it does connect to the common ground bus. On the gray connector, note that socket 28 is completely missing, so that pin 28 of the drive attached to the gray connector will be open. On the black connector, sockets 28 and 34 are completely normal, so that pins 28 and 34 of the drive attached to the black connector will be connected to the cable. Pin 28 of the black drive reaches pin 28 of the host receptacle but not pin 28 of the gray drive, while pin 34 of the black drive reaches pin 34 of the gray drive but not pin 34 of the host. Instead, pin 34 of the host is grounded.
The standard dictates color-coded connectors for easy identification by both installer and cable maker. All three connectors are different from one another. The blue (host) connector has the socket for pin 34 connected to ground inside the connector but not attached to any conductor of the cable. Since the old 40 conductor cables do not ground pin 34, the presence of a ground connection indicates that an 80 conductor cable is installed. The wire for pin 34 is attached normally on the other types and is not grounded. Installing the cable backwards (with the black connector on the system board, the blue connector on the remote device and the gray connector on the center device) will ground pin 34 of the remote device and connect host pin 34 through to pin 34 of the center device. The gray center connector omits the connection to pin 28 but connects pin 34 normally, while the black end connector connects both pins 28 and 34 normally.

Multiple devices on a cable

If two devices attach to a single cable, one must be designated as device 0 (commonly referred to as master) and the other as device 1 (slave). This distinction is necessary to allow both drives to share the cable without conflict. The master drive is the drive that usually appears "first" to the computer's BIOS and/or operating system. On old BIOSes (Intel 486 era and older), the drives are often referred to by the BIOS as "C" for the master and "D" for the slave following the way DOS would refer to the active primary partitions on each.
The mode that a drive must use is often set by a jumper setting on the drive itself, which must be manually set to master or slave. If there is a single device on a cable, it should be configured as master. However, some hard drives have a special setting called single for this configuration (Western Digital, in particular). Also, depending on the hardware and software available, a single drive on a cable can work reliably even though configured as the slave drive (this configuration is most often seen when a CD ROM has a channel to itself).

Cable select

A drive mode called cable select was described as optional in ATA-1 and has come into fairly widespread use with ATA-5 and later. A drive set to "cable select" automatically configures itself as master or slave, according to its position on the cable. Cable select is controlled by pin 28. The host adapter grounds this pin; if a device sees that the pin is grounded, it becomes the master device; if it sees that pin 28 is open, the device becomes the slave device.
This setting is usually chosen by a jumper setting on the drive called "cable select", usually marked CS, which is separate from the "master" or "slave" setting.
Note that if two drives are configured as master and slave manually, this configuration does not need to correspond to their position on the cable. Pin 28 is only used to let the drives know their position on the cable; it is not used by the host when communicating with the drives.
With the 40-wire cable it was very common to implement cable select by simply cutting the pin 28 wire between the two device connectors; putting the slave device at the end of the cable, and the master on the middle connector. This arrangement eventually was standardized in later versions. If there is just one device on the cable, this results in an unused stub of cable, which is undesirable for physical convenience and electrical reasons. The stub causes signal reflections, particularly at higher transfer rates.
Starting with the 80-wire cable defined for use in ATAPI5/UDMA4, the master device goes at the end of the 18-inch (460 mm) cable—the black connector—and the slave device goes on the middle connector—the gray one—and the blue connector goes onto the motherboard. So, if there is only one (master) device on the cable, there is no cable stub to cause reflections. Also, cable select is now implemented in the slave device connector, usually simply by omitting the contact from the connector body.

Master and slave clarification

Although they are in extremely common use, the terms "master" and "slave" do not actually appear in current versions of the ATA specifications. The two devices are simply referred to as "device 0" and "device 1", respectively, in ATA-2 and later.
It is a common myth that the controller on the master drive assumes control over the slave drive, or that the master drive may claim priority of communication over the other device on the channel. In fact, the drivers in the host operating system perform the necessary arbitration and serialization, and each drive's onboard controller operates independently of the other.
The terms "master" and "slave" have not been without controversy. In 2003, the County of Los Angeles, California, US requested that, when possible, supp

LINUX UBUNTU OPERATING SYSTEM

2011-03-16T01:10:00.000-07:00

Ubuntu (operating system)



Ubuntu 10.10 (Maverick Meerkat)
Company / developer	Canonical Ltd. / Ubuntu Foundation
OS family	Unix-like
Working state	Current
Source model	Free and open source software (with exceptions)^[1]^[2]
Initial release	20 October 2004 (2004-10-20)
Latest stable release	10.10 (Maverick Meerkat) / 10 October 2010; 5 months ago^[3] (2010-10-10)
Latest unstable release	11.04 (Natty Narwhal) Alpha 3 / 3 March 2011; 12 days ago^[4] (2011-03-03)
Available language(s)	Multilingual (more than 55)
Update method	APT (front-ends available)
Package manager	dpkg (front-ends like Synaptic available)
Supported platforms	i386, amd64
Kernel type	Linux (Monolithic-based Hybrid)
Userland	GNU
Default user interface	GNOME
License	Mainly the GNU GPL and various free software other licenses / plus proprietary binary blobs.^[1]^[2]
Official website	ubuntu.com

Ubuntu (pronounced /ʊˈbʊntuː/)^[5]^[6] is a computer operating system based on the Debian GNU/Linux distribution and distributed as free and open source software. It is named after the Southern African philosophy of Ubuntu ("humanity towards others").^[7]

With an estimated global usage of more than 12 million users,^[8] Ubuntu is designed primarily for desktop use, although netbook and server editions exist as well.^[9] Web statistics suggest that Ubuntu's share of Linux desktop usage is about 50%,^[10]^[11] and indicate upward-trending usage as a web server.^[12]

Ubuntu is sponsored by the UK-based company Canonical Ltd., owned by South African entrepreneur Mark Shuttleworth. Canonical generates revenue by selling technical support and services tied to Ubuntu, while the operating system itself is entirely free of charge.

1 History and development process
2 Features
- 2.1 System requirements
- 2.2 Installation
3 Package classification and support
- 3.1 Availability of third-party software
4 Releases
5 Variants
6 Development
7 Reception
8 Local Communities (LoCos)
9 Vendor support
10 See also
11 Bibliography
12 References
13 External links

History and development process

Ubuntu is a fork of the Debian project's codebase. The original aim of the Ubuntu team was to create an easy-to-use (freedom for users rather than freedom for programmers) Linux desktop with new releases scheduled on a predictable six-month basis, resulting in a more frequently updated system.^[13]^[14]

Ubuntu's first release was on 20 October 2004. Since then, Canonical has released new versions of Ubuntu every six months^[15] with commitment to support each release for eighteen months by providing security fixes, patches to critical bugs and minor updates to programs. It was decided that every fourth release, issued on a two-year basis, would receive long-term support (LTS).^[13] LTS releases are supported for three years on the desktop and five years on the server.^[15]

The latest LTS release is Ubuntu 10.04 (Lucid Lynx), released on 29 April 2010, while the latest normal release is Ubuntu 10.10 (Maverick Meerkat), released on 10 October 2010.

Ubuntu packages are based on packages from Debian's unstable branch: both distributions use Debian's deb package format and package management tools (APT and Synaptic). Debian and Ubuntu packages are not necessarily binary compatible with each other, however, and sometimes .deb packages may need to be rebuilt from source to be used in Ubuntu.^[16] Many Ubuntu developers are also maintainers of key packages within Debian. Ubuntu cooperates with Debian by pushing changes back to Debian,^[17]Ian Murdock, the founder of Debian, has expressed concern about Ubuntu packages potentially diverging too far from Debian to remain compatible.^[18] Before release, packages are imported from Debian Unstable frozen, and packagers then work to ensure that the frozen features interoperate well together. although there has been criticism that this does not happen often enough. In the past, continuously and merged with Ubuntu-specific modifications. A month before release, imports are

Ubuntu is currently funded by Canonical Ltd. On 8 July 2005, Mark Shuttleworth and Canonical Ltd. announced the creation of the Ubuntu Foundation and provided an initial funding of US$10 million. The purpose of the foundation is to ensure the support and development for all future versions of Ubuntu. Mark Shuttleworth describes the foundation as an "emergency fund" (in case Canonical's involvement ends).^[19]

On 12 March 2009, Ubuntu announced developer support for 3rd party cloud management platforms, such as for those used at Amazon EC2.^[20]

Features

Ubuntu is composed of many software packages, the vast majority are distributed under a free software license. The only exceptions are some proprietary hardware drivers^[21] which are needed to safeguard every individual's freedom to use Ubuntu. The main license used is the GNU General Public License GNU Lesser General Public License (GNU LGPL), explicitly declares that users are free to run, copy, distribute, study, change, develop and improve the software. On the other hand, there is also proprietary software available that can run on Ubuntu. Ubuntu focuses on usability, security and stability.^[22] The Ubiquity installer allows Ubuntu to be installed to the hard disk from within the Live CD environment, without the need for restarting the computer prior to installation. Ubuntu also emphasizes accessibility and internationalization to reach as many people as possible. Beginning with 5.04, UTF-8 became the default character encoding,^[23] which allows for support of a variety of non-Roman scripts. As a security feature, the sudo tool is used to assign temporary privileges for performing administrative tasks, allowing the root account to remain locked, and preventing inexperienced users from inadvertently making catastrophic system changes or opening security holes.^[24] PolicyKit is also being widely implemented into the desktop to further harden^[jargon]principle of least privilege. (GNU GPL) which, along with the the system through the

Ubuntu comes installed with a wide range of software that includes OpenOffice, Firefox, Empathy Pidgin in versions before 9.10), Transmission, GIMP (in versions prior to 10.04), and several lightweight games (such as Sudoku and chess). Additional software that is not installed by default can be downloaded and installed using the Ubuntu Software Center^[25] or the package manager Synaptic, which come pre-installed. Ubuntu allows networking ports to be closed using its firewall, with customized port selection available. End-users can install Gufw (GUI for Uncomplicated Firewall) and keep it enabled.^[26] GNOME (the current default desktop) offers support for more than 46 languages.^[27] Ubuntu can also run many programs designed for Microsoft Windows (such as Microsoft Office), through Wine or using a Virtual Machine (such as VMware Workstation or VirtualBox). For the upcoming 11.04 release, Canonical intends to drop the GNOME Shell as the default desktop environment in favor of Unity, a graphical interface it first developed for the netbook edition of Ubuntu.^[28] (

Ubuntu, unlike Debian, compiles their packages using gcc features such as PIE and Buffer overflow protection to harden their software.^[29] These extra features greatly increase security at the performance expense of 1% in 32 bit and 0.01% in 64 bit.^[30]

System requirements

The desktop version of Ubuntu currently supports the x86 32 bit and 64 bit architectures. Unofficial support is available for the PowerPC,^[31] IA-64 (Itanium) and PlayStation 3 architectures (note however that Sony officially removed support for OtherOS on the PS3 with firmware 3.21, released on 1 April 2010), as well as ARM mobile processors (see HTC HD2).^[32] A supported GPU is required to enable desktop visual effects.

Current Minimum Requirements^[33]^[34]^[35]	Server	Desktop
Processor (x86) with the i686 instruction set^[36]	300 MHz	1 GHz
Memory	128 MB	512 MB
Hard Drive (free space)	1 GB	5 GB
Monitor Resolution	640×480	1024×768

Installation

Ubuntu Desktop 10.10 Live CD

Installation of Ubuntu is generally performed with the Live CD. The Ubuntu OS can be run directly from the CD (sometimes with a significant performance loss), allowing a user to "test-drive" the OS for hardware compatibility and driver support. The CD also contains the Ubiquity installer,^[37] which then can guide the user through the permanent installation process. CD images of all current and past versions are available for download at the Ubuntu web site.^[38] Installing from the CD requires a minimum of 256 MiB of RAM.

Users can download a disk image (.iso) of the CD, which can then either be written to a physical medium (CD or DVD), or optionally run directly from a hard drive (via UNetbootin or GRUB). Ubuntu is also available on ARM, PowerPC, SPARC, and IA-64 platforms, although none are officially supported.^[39]

Canonical offers Ubuntu^[40] and Kubuntu^[41] Live installation CDs at no cost, including paid postage for destinations in most countries around the world (via a service called ShipIt). Various third-party programs such as remastersys and Reconstructor are available to create customised copies of the Ubuntu Live CDs.

A Microsoft Windows migration tool, called Migration Assistant (introduced in April 2007),^[42] can be used to import bookmarks, desktop background (wallpaper), and various settings from an existing MS Windows installation into a new Ubuntu installation.^[43]

Ubuntu and Kubuntu can be booted and run from a USB Flash drive (as long as the BIOS supports booting from USB), with the option of saving settings to the flashdrive. This allows a portable installation that can be run on any PC which is capable of booting from a USB drive.^[44] In newer versions of Ubuntu, the USB creator program is available to install Ubuntu on a USB drive (with or without a LiveCD disc).

Wubi, which is included as an option on the Live CD,^[45] allows Ubuntu to be installed and run from within a virtual Windows loop device (as a large image file that is managed like any other Windows program via the Windows Control Panel). This method requires no partitioning of a Windows user's hard drive. Wubi also makes use of the Migration Assistant to import users' settings. It is only useful for Windows users and it also incurs a slight performance loss.

Package classification and support

Ubuntu divides all software into four domains to reflect differences in licensing and the degree of support available.^[46] Some unsupported applications receive updates from community members, but not from Canonical Ltd.

	Free software	Non-free software
Supported	Main	Restricted
Unsupported	Universe	Multiverse

Free software includes only software that has met the Ubuntu licensing requirements,^[21] which roughly correspond to the Debian Free Software Guidelines. Exceptions, however, include firmware and fonts, in the Main category, because although they are not allowed to be modified, their distribution is otherwise unencumbered.^{[citation needed]}

Non-free software is usually unsupported (Multiverse), but some exceptions (Restricted) are made for important non-free software. Supported non-free software includes device drivers that can be used to run Ubuntu on some current hardware, such as binary-only graphics card drivers. The level of support in the Restricted category is more limited than that of Main, because the developers may not have access to the source code. It is intended that Main and Restricted should contain all software needed for a general-use GNU/Linux system.^{[citation needed]} Alternative programs for the same tasks and programs for specialized applications are placed in the Universe and Multiverse categories.

In addition to the above, in which the software does not receive new features after an initial release, Ubuntu Backports is an officially recognized repository for backporting newer software from later versions of Ubuntu.^[47] The repository is not comprehensive; it consists primarily of user-requested packages, which are approved if they meet quality guidelines. Backports receives no support at all from Canonical, and is entirely community-maintained.

The -updates repository provides updates to stable releases of Ubuntu and are generally installed through update-manager. Each release is given its own -updates repository (e.g. intrepid-updates). The repository is supported by Canonical Ltd. for packages in main and restricted, and by the community for packages in universe and multiverse. All updates to the repository must meet certain requirements and go through the -proposed repository before being made available to the public.^[48] Updates will continue to be available until the end of life for the release.

In addition to the -updates repository, the unstable -proposed repository contains uploads which must be confirmed before being copied into -updates. All updates must go through this process to ensure that the patch does truly fix the bug and there is no risk of regression.^[49] Updates in -proposed are confirmed by either Canonical or members of the community.

Canonical's partner repository lets vendors of proprietary software deliver their products to Ubuntu users at no cost through the same familiar tools for installing and upgrading software.^[50] The software in the partner repository is officially supported with security and other important updates by its respective vendors. Canonical supports the packaging of the software for Ubuntu^[50]^[51]^[52] and provides guidance to vendors.^[50] The partner repository is disabled by default and can be enabled by the user.^[53] Some popular products distributed via the partner repository as of August 2010 are Adobe Flash Player, Adobe Reader, Skype and Sun Java.

Availability of third-party software

See also: Medibuntu and GetDeb

Ubuntu has a certification system for third party software.^[54] Some third-party software that does not limit distribution is included in Ubuntu's multiverse component. The package ubuntu-restricted-extras MP3 and DVD Microsoft TrueType core fonts, Sun's Java runtime environment, Adobe's Flash Player codecs, and unrar, an unarchiver for files compressed in the RAR file format. additionally contains software that may be legally restricted, including support for playback, plugin, many common audio/video

Additionally, several third party application suites are available for purchase through the Canonical web-based store,^{[citation needed]} including software for DVD playback and media codecs.Releases

Main article: List of Ubuntu

releases

Version	Code name	Release date	Supported until
Version	Code name	Release date	Desktop	Server
4.10	Warty Warthog	2004-10-20	2006-04-30
5.04	Hoary Hedgehog	2005-04-08	2006-10-31
5.10	Breezy Badger	2005-10-13	2007-04-13
6.06 LTS	Dapper Drake	2006-06-01	2009-07-14	2011-06
6.10	Edgy Eft	2006-10-26	2008-04-25
7.04	Feisty Fawn	2007-04-19	2008-10-19
7.10	Gutsy Gibbon	2007-10-18	2009-04-18
8.04 LTS	Hardy Heron	2008-04-24	2011-04	2013-04
8.10	Intrepid Ibex	2008-10-30	2010-04-30
9.04	Jaunty Jackalope	2009-04-23	2010-10-23
9.10	Karmic Koala	2009-10-29	2011-04
10.04 LTS	Lucid Lynx	2010-04-29	2013-04	2015-04
10.10	Maverick Meerkat	2010-10-10	2012-04
11.04	Natty Narwhal	2011-04-28	2012-10
11.10	Oneiric Ocelot	2011-10-?	2013-04
Colour		Meaning
Red		Release no longer supported
Green		Release still supported
Blue		Future release

Each Ubuntu release has a version number that consists of the year and month number of the release.^[55] For example, the first release was Ubuntu 4.10 as it was released on 20 October 2004. Version numbers for future versions are provisional; if the release is delayed the version number changes accordingly.

Ubuntu releases are also given alliterative code names, using an adjective and an animal (e.g., "Dapper Drake" and "Intrepid Ibex"). With the exception of the first three releases, code names are in alphabetical order, allowing a quick determination of which release is newer. "We might skip a few letters, and we'll have to wrap eventually." says Mark Shuttleworth while describing the naming scheme.^{[citation needed]} Commonly, Ubuntu releases are referred to using only the adjective portion of the code name.^[56]

Releases are timed to be approximately one month after GNOME releases (which in turn are about one month after releases of X.org). Consequently, every Ubuntu release comes with an updated version of both GNOME and X.

Upgrades between releases have to be done from one release to the next release (e.g. Ubuntu 10.04 to Ubuntu 10.10) or from one LTS release to the next LTS release (e.g. Ubuntu 8.04 LTS to Ubuntu 10.04 LTS).^[57]

The current release is 10.10 (Maverick Meerkat), released on 10 October 2010 (10/10/10). This is a departure from the traditional schedule of releasing at the end of October to get "the perfect 10",^[58] and a playful reference to The Hitchhiker's Guide to the Galaxy, since, in binary, 101010 is equal to the number 42, the "Answer to the Ultimate Question of Life, the Universe and Everything" within the series.^[59]

Ubuntu 11.04 planned for 28 April 2011 is code named "Natty Narwhal".^[60]^[61]

Variants

See also: List of Ubuntu-based Linux distributions

Kubuntu is an official variant of the Ubuntu distribution which uses the KDE Plasma Workspaces.

Official Ubuntu editions, which are created and maintained by Canonical and the Ubuntu community and receive full support from Canonical, its partners and the Community, are the following:^[62]^[63]

Ubuntu Desktop Edition, designed for desktop and laptop PCs.
Ubuntu Netbook Edition, (formerly Ubuntu Netbook Remix)^[64]^[65] designed for netbooks and other ultra-portables.^[66] Ubuntu Netbook Edition is set to be discontinued, as the Unity Interface will be used as default in both Desktop and Netbook Editions.^[67]
Ubuntu Server Edition, made for use in servers.^[68]

There are many Ubuntu variants (or derivates) based on the official Ubuntu editions. These Ubuntu variants install a set of packages that differ from the official Ubuntu distributions.

The variants recognized by Canonical as contributing significantly towards the Ubuntu project are the following:^[62]

Edubuntu, a GNOME-based subproject and add-on for Ubuntu, designed for school environments and home users.^[69]
Kubuntu, a desktop distribution using the KDE Plasma Workspaces desktop environment rather than GNOME.
Mythbuntu, designed for creating a home theater PC with MythTV and uses the Xfce desktop environment.
Ubuntu Studio, a distribution made for professional video and audio editing, comes with higher-end free editing software and is a DVD .iso image unlike the Live CD the other Ubuntu distributions use.
Xubuntu, a distribution based on the Xfce desktop environment instead of GNOME, designed to run more efficiently on low-specification computers.

Mythbuntu, Ubuntu Studio, Xubuntu and Gobuntu are not commercially supported by Canonical.^[70]

Other variants are created and maintained by individuals and organizations outside of Canonical and they are self governed projects that work more or less closely with the Ubuntu community.^[63] Some of the variants, such as Lubuntu, a lightweight variant using LXDE, have the explicit goal of earning official endorsement from Canonical.^[71]

Development

UDS Maverick Group Photo

The Ubuntu Developer Summit is a gathering of software developers which occurs prior to the release of a new public version of Ubuntu.^[72]

At the beginning of a new development cycle, Ubuntu developers from around the world gather to help shape and scope the next release of Ubuntu. The summit is open to the public, but it is not a conference, exhibition or other audience-oriented event. Rather, it is an opportunity for Ubuntu developers, who usually collaborate online, to work together in person on specific tasks.

Reception

Chris Kenyon, vice president for OEM at Canonical Ltd., indicates that because of a lack of registration, any numbers provided for Ubuntu distributions should be treated as estimates.^[73] Nevertheless, a number of estimates and the results of surveys have been provided. In an August 2007 survey of 38,500 visitors on DesktopLinux.com, Ubuntu was the most popular distribution with 30.3% of respondents claiming to use it.^[74] In January 2009, The New York Times reported that Ubuntu had over ten million users. In June 2009 ZDNet reported, "Worldwide, there are 13 million active Ubuntu users with use growing faster than any other distribution.",^[75]^[76] though Kenyon provided a more conservative estimate of 12 million users in April 2010.^[73]

Ubuntu was awarded the Reader Award for best Linux distribution at the 2005 LinuxWorld Conference and Expo in London,^[77] received favorable reviews in online and print publications,^[78]^[79]InfoWorld's 2007 Bossie Award for and has won Best Open Source Client OS.^[80] In early 2008 PC World named Ubuntu the "best all-around Linux distribution available today", though it criticized the lack of an integrated desktop effects manager.^[81]

The public sector has also made use of Ubuntu. The Ministry of Education and Science of the Republic of Macedonia deployed more than 180,000 Ubuntu GNU/Linux based classroom desktops, and has encouraged every student in the country to use Ubuntu-powered computer workstations.^[82] In the beginning of 2008, having successfully deployed 13,000 Fedora Linux systems in schools in the Philippines, ASI, an independent Linux consultant company, was contracted to provide 10,000 Ubuntu systems for schools.^[83] The French police, having already started using open source software in 2005 by replacing Microsoft Office with OpenOffice.org in 2005, decided to transition to Ubuntu from Windows XP after the release of Windows Vista in 2006.^[84] By March 2009, the Gendarmerie Nationale had already switched 5000 workstations to Ubuntu.^[84] Based on the success of that transition, it planned to switch 15,000 more over by the end of 2009 and to have switched all 90,000 workstations over by 2015.^[84] Lt. Colonel Guimard announced that the move was very easy and allowed for a 70% saving on the IT budget without having to reduce its capabilities.^[84]

In 2008, Jamie Hyneman, co-host of the television series Mythbusters, advocated Linux (specifically giving the example of Ubuntu) as an alternative to proprietary software, citing software bloat as a major hurdle in proprietary operating systems.^[85]

Local Communities (LoCos)

In an effort to reach out to users who are less technical, and to foster a sense of community around the distribution, Local Communities,^[86] better known as "LoCos", have been established throughout the world. Originally, each country had one LoCo Team. However, in some areas, most notably, the United States, each state or province may establish a team. A LoCo Council approves teams based upon their efforts to either aid in the development or the promotion of Ubuntu.

Vendor support

A number of vendors offer computers with Ubuntu pre-installed, including Hasee, Dell,^[87] Tesco, OP3, Gliese IT, System76,^[88] Sharp Corporation^[89] and the South African company Bravium Computers.^[90] Dell and System76 customers are able to choose between 30-day, three-month, and yearly Ubuntu support plans through Canonical.^[91] Dell computers (running Ubuntu 10.04) include extra support for ATI Video Graphics, Dell Wireless, Fingerprint Readers, HDMI, Bluetooth, DVD Playback (using LinDVD), and MP3/WMA/WMV.^[92]

KEYBOARD

2011-03-02T09:56:00.000-08:00

Computer keyboard

A laptop's keyboard.

In computing, a keyboard is a typewriter keyboard, which uses an arrangement of buttons or keys, to act as mechanical levers or electronic switches. With the decline of punch cards and paper tape, interaction via teletype-style keyboards became the main input device for computers.
Despite the development of alternative input devices, such as the mouse, touchscreen, pen devices, character recognition and voice recognition, the keyboard remains the most commonly used and most versatile device used for direct (human) input into computers.
A keyboard typically has characters engraved or printed on the keys and each press of a key typically corresponds to a single written symbol. However, to produce some symbols requires pressing and holding several keys simultaneously or in sequence. While most keyboard keys produce letters, numbers or signs (characters), other keys or simultaneous key presses can produce actions or computer commands.
In normal usage, the keyboard is used to type text and numbers into a word processor, text editor or other program. In a modern computer, the interpretation of key presses is generally left to the software. A computer keyboard distinguishes each physical key from every other and reports all key presses to the controlling software. Keyboards are also used for computer gaming, either with regular keyboards or by using keyboards with special gaming features, which can expedite frequently used keystroke combinations. A keyboard is also used to give commands to the operating system of a computer, such as Windows' Control-Alt-Delete combination, which brings up a task window or shuts down the machine. It is the only way to enter commands on a command-line interface.

Keyboard types

One factor determining the size of a keyboard is the presence of duplicate keys, such as a separate numeric keyboard, for convenience.
Further the keyboard size depends on the extent to which a system is used where a single action is produced by a combination of subsequent or simultaneous keystrokes (with modifier keys, see below), or multiple pressing of a single key. A keyboard with few keys is called a keypad. See also text entry interface.
Another factor determining the size of a keyboard is the size and spacing of the keys. Reduction is limited by the practical consideration that the keys must be large enough to be easily pressed by fingers. Alternatively a tool is used for pressing small keys.

Standard

Standard "full-travel" alphanumeric keyboards have keys that are on three-quarter inch centers (0.750 inches, 19.05 mm), and have a key travel of at least 0.150 inches (3.81 mm). Desktop computer keyboards, such as the 101-key US traditional keyboards or the 104-key Windows keyboards, include alphabetic characters, punctuation symbols, numbers and a variety of function keys. The internationally-common 102/105 key keyboards have a smaller 'left shift' key and an additional key with some more symbols between that and the letter to its right (usually Z or Y). Also the 'enter' key is usually shaped differently.^[1] Computer keyboards are similar to electric-typewriter keyboards but contain additional keys. Standard USB keyboards can also be connected to some non-desktop devices. ^[2]

Laptop-size

Keyboards on laptops and notebook computers usually have a shorter travel distance for the keystroke and a reduced set of keys. They may not have a numerical keypad, and the function keys may be placed in locations that differ from their placement on a standard, full-sized keyboard.

The keyboards on laptops have a shorter travel distance and (usually) a reduced set of keys.

Thumb-sized

Smaller keyboards have been introduced for laptops (mainly nettops), PDAs, smartphones, or users who have a limited workspace.
A chording keyer allows pressing several keys simultaneously. For example, the GKOS keyboard has been designed for small wireless devices. Other two-handed alternatives more akin to a game controller, such as the AlphaGrip, are also used as a way to input data and text.
A "thumbboard" (thumbing) is used in some personal digital assistants such as the Palm Treo and BlackBerry and some Ultra-Mobile PCs such as the OQO.
Numeric keyboards contain only numbers, mathematical symbols for addition, subtraction, multiplication, and division, a decimal point, and several function keys. They are often used to facilitate data entry with smaller keyboards that do not have a numeric keypad, commonly those of laptop computers. These keys are collectively known as a numeric pad, numeric keys, or a numeric keypad, and it can consist of the following types of keys:

arithmetic operators such as +, -, *, /
numeric digits 0–9
cursor arrow keys
navigation keys such as Home, End, PgUp, PgDown, etc.
Num Lock button, used to enable or disable the numeric pad
enter key.

Non-standard layout and special-use types

Chorded

While other keyboards generally associate one action with each key, chorded keyboards associate actions with combinations of key presses. Since there are many combinations available, chorded keyboards can effectively produce more actions on a board with fewer keys. Court reporters' stenotype machines use chorded keyboards to enable them to enter text much faster by typing a syllable with each stroke instead of one letter at a time. The fastest typists (as of 2007) use a stenograph, a kind of chorded keyboard used by most court reporters and closed-caption reporters. Some chorded keyboards are also made for use in situations where fewer keys are preferable, such as on devices that can be used with only one hand, and on small mobile devices that don't have room for larger keyboards. Chorded keyboards are less desirable in many cases because it usually takes practice and memorization of the combinations to become proficient.

Software

Software keyboards or on-screen keyboards often take the form of computer programs that display an image of a keyboard on the screen. Another input device such as a mouse or a touchscreen can be used to operate each virtual key to enter text. Software keyboards have become very popular in touchscreen enabled cell phones, due to the additional cost and space requirements of other types of hardware keyboards. Microsoft Windows, Mac OS X, and some varieties of Linux include on-screen keyboards that can be controlled with the mouse.

foldable

Further information: Flexible electronics

A foldable keyboard.

Foldable (also called flexible) keyboards are made of soft plastic or silicone which can be rolled or folded on itself for travel.^[3] When in use, these keyboards can conform to uneven surfaces, and are more resistant to liquids than standard keyboards. These can also be connected to portable devices and smartphones. Some models can be fully immersed in water, making them popular in hospitals and laboratories, as they can be disinfected.

Projection/laser

Projection keyboards project an image of keys, usually with a laser, onto a flat surface. The device then uses a camera or infrared sensor to "watch" where the user's fingers move, and will count a key as being pressed when it "sees" the user's finger touch the projected image. Projection keyboards can simulate a full size keyboard from a very small projector. Because the "keys' are simply projected images, they cannot be felt when pressed. Users of projected keyboards often experience increased discomfort in their fingertips because of the lack of "give" when typing. A flat, non-reflective surface is also required for the keys to be projected onto. Most projection keyboards are made for use with PDAs due to their small form factor.

Optical keyboard technology

Also known as photo-optical keyboard, light responsive keyboard, photo-electric keyboard and optical key actuation detection technology.
An optical keyboard technology utilizes light emitting devices and photo sensors to optically detect actuated keys. Most commonly the emitters and sensors are located in the perimeter, mounted on a small PCB. The light is directed from side to side of the keyboard interior and it can only be blocked by the actuated keys. Most optical keyboards require at least 2 beams (most commonly vertical beam and horizontal beam) to determine the actuated key. Some optical keyboards use a special key structure that blocks the light in a certain pattern, allowing only one beam per row of keys (most commonly horizontal beam).

Further information: Keyboard technology

Layout

Alphabetic

Main article: Keyboard layout

The 104-key PC US English QWERTY keyboard layout evolved from the standard typewriter keyboard, with extra keys for computing.

The Dvorak Simplified Keyboard layout arranges keys so that frequently used keys are easiest to press, which reduces muscle fatigue when typing common English.

There are a number of different arrangements of alphabetic, numeric, and punctuation symbols on keys. These different keyboard layouts arise mainly because different people need easy access to different symbols, either because they are inputting text in different languages, or because they need a specialized layout for mathematics, accounting, computer programming, or other purposes. The United States keyboard layout is used as default in the currently most popular operating systems: Windows,^[4] Mac OS X^[5] and Linux.^[6]^[7] Most of the more common keyboard layouts (QWERTY-based and similar) were designed in the era of the mechanical typewriters, so their ergonomics had to be slightly compromised in order to tackle some of the mechanical limitations of the typewriter.
As the letter-keys were attached to levers that needed to move freely, inventor Christopher Sholes developed the QWERTY layout to reduce the likelihood of jamming. With the advent of computers, lever jams are no longer an issue, but nevertheless, QWERTY layouts were adopted for electronic keyboards because they were widely used. Alternative layouts such as the Dvorak Simplified Keyboard are not in widespread use.
The QWERTZ layout is widely used in Germany and much of Central Europe. The main difference between it and QWERTY is that Y and Z are swapped, and most special characters such as brackets are replaced by diacritical characters.
Another situation takes place with “national” layouts. Keyboards designed for typing in Spanish have some characters shifted, to release the space for Ñ ñ; similarly, those for French and other European languages may have a special key for the character Ç ç . The AZERTY layout is used in France, Belgium and some neighbouring countries. It differs from the QWERTY layout in that the A and Q are swapped, the Z and W are swapped, and the M is moved from the right of N to the right of L (where colon/semicolon is on a US keyboard). The digits 0 to 9 are on the same keys, but to be typed the shift key must be pressed. The unshifted positions are used for accented characters.
Keyboards in many parts of Asia may have special keys to switch between the Latin character set and a completely different typing system. In Japan, keyboards often can be switched between Japanese and the Latin alphabet, and the character ¥ (the Yen currency) is used instead of "\"^{[citation needed]}. In the Arab world, keyboards can often be switched between Arabic and Latin characters.
In bilingual regions of Canada and in the French-speaking province of Québec, keyboards can often be switched between an English and a French-language keyboard; while both keyboards share the same QWERTY alphabetic layout, the French-language keyboard enables the user to type accented vowels such as "é" or "à" with a single keystroke. Using keyboards for other languages leads to a conflict: the image on the key does not correspond to the character. In such cases, each new language may require an additional label on the keys, because the standard keyboard layouts do not share even similar characters of different languages (see the example in the figure above).

Key types

Alphanumeric

A Hebrew keyboard lets the user type in both Hebrew and the Latin alphabet.

A Greek keyboard lets the user type in both Greek and the Latin alphabet (Macbook Pro).

Alphabetical, numeric, and punctuation keys are used in the same fashion as a typewriter keyboard to enter their respective symbol into a word processing program, text editor, data spreadsheet, or other program. Many of these keys will produce different symbols when modifier keys or shift keys are pressed. The alphabetic characters become uppercase when the shift key or Caps Lock key is depressed. The numeric characters become symbols or punctuation marks when the shift key is depressed. The alphabetical, numeric, and punctuation keys can also have other functions when they are pressed at the same time as some modifier keys.
The Space bar is a horizontal bar in the lowermost row, which is significantly wider than other keys. Like the alphanumeric characters, it is also descended from the mechanical typewriter. Its main purpose is to enter the space between words during typing. It is large enough so that a thumb from either hand can use it easily. Depending on the operating system, when the space bar is used with a modifier key such as the control key, it may have functions such as resizing or closing the current window, half-spacing, or backspacing. In computer games and other applications the key has myriad uses in addition to its normal purpose in typing, such as jumping and adding marks to check boxes. In certain programs for playback of digital video, the space bar is used for pausing and resuming the playback.

Modifiers

Modifier keys are special keys that modify the normal action of another key, when the two are pressed in combination. For example, <Alt> + <F4> in Microsoft Windows will close the program in an active window. In contrast, pressing just <F4> will probably do nothing, unless assigned a specific function in a particular program. By themselves, modifier keys usually do nothing.

The Ctrl and Alt keys are important modifier keys.

The most widely-used modifier keys include the Control key, Shift key and the Alt key. The AltGr key is used to access additional symbols for keys that have three symbols printed on them. On the Macintosh and Apple keyboards, the modifier keys are the Option key and Command key, respectively. On MIT computer keyboards, the Meta key is used as a modifier and for Windows keyboards, there is a Windows key. Compact keyboard layouts often use a Fn key. "Dead keys" allow placement of a diacritic mark, such as an accent, on the following letter (e.g., the Compose key).

A Space-cadet keyboard has many modifier keys.

The Enter/Return key typically causes a command line, window form or dialog box to operate its default function, which is typically to finish an "entry" and begin the desired process. In word processing applications, pressing the enter key ends a paragraph and starts a new one.

Navigation and typing modes

Navigation keys include a variety of keys which move the cursor to different positions on the screen. Arrow keys are programmed to move the cursor in a specified direction; page scroll keys, such as the 'Page Up and Page Down keys', scroll the page up and down. The Home key is used to return the cursor to the beginning of the line where the cursor is located; the End key puts the cursor at the end of the line. The Tab key advances the cursor to the next tab stop.
The Insert key is mainly used to switch between overtype mode, in which the cursor overwrites any text that is present on and after its current location, and insert mode, where the cursor inserts a character at its current position, forcing all characters past it one position further. The Delete key discards the character ahead of the cursor's position, moving all following characters one position "back" towards the freed place. On many notebook computer keyboards the key labeled Delete (sometimes Delete and Backspace are printed on the same key) serves the same purpose as a Backspace key. The Backspace key deletes the preceding character.
Lock keys lock part of a keyboard, depending on the settings selected. The lock keys are scattered around the keyboard. Most styles of keyboards have three LEDs indicating which locks are enabled, in the upper right corner above the numpad. The lock keys include Scroll lock, Num lock (which allows the use of the numeric keypad), and Caps lock.

System commands

The SysRq / Print screen commands often share the same key. SysRq was used in earlier computers as a "panic" button to recover from crashes. The Print screen command used to capture the entire screen and send it to the printer, but in the present it usually puts a screenshot in the clipboard. The Break key/Pause key no longer has a well-defined purpose. Its origins go back to teletype users, who wanted a key that would temporarily interrupt the communications line. The Break key can be used by software in several different ways, such as to switch between multiple login sessions, to terminate a program, or to interrupt a modem connection.
In programming, especially old DOS-style BASIC, Pascal and C, Break is used (in conjunction with Ctrl) to stop program execution. In addition to this, Linux and variants, as well as many DOS programs, treat this combination the same as Ctrl+C. On modern keyboards, the break key is usually labeled Pause/Break. In most Windows environments, the key combination Windows key+Pause brings up the system properties.
The Escape key (often abbreviated Esc) is used to initiate an escape sequence. As most computer users no longer are concerned with the details of controlling their computer's peripherals, the task for which the escape sequences were originally designed, the escape key was appropriated by application programmers, most often to "escape" or back out of a mistaken command. This use continues today in Microsoft Windows's use of escape as a shortcut in dialog boxes for No, Quit, Exit, Cancel, or Abort.
A common application today of the Esc key is as a shortcut key for the Stop button in many web browsers. On machines running Microsoft Windows, prior to the implementation of the Windows key on keyboards, the typical practice for invoking the "start" button was to hold down the control key and press escape. This process still works in Windows 2000, XP, Windows Vista and Windows 7.
The Menu key or Application key is a key found on Windows-oriented computer keyboards. It is used to launch a context menu with the keyboard rather than with the usual right mouse button. The key's symbol is a small icon depicting a cursor hovering above a menu. This key was created at the same time as the Windows key. This key is normally used when the right mouse button is not present on the mouse. Some Windows public terminals do not have a Menu key on their keyboard to prevent users from right-clicking (however, in many windows applications, a similar functionality can be invoked with the Shift+F10 keyboard shortcut).

Miscellaneous

Multimedia buttons on some keyboards give quick access to the Internet or control the volume of the speakers.

Many, but not all, computer keyboards have a numeric keypad to the right of the alphabetic keyboard which contains numbers, basic mathematical symbols (e.g., addition, subtraction, etc.), and a few function keys. On Japanese/Korean keyboards, there may be Language input keys. Some keyboards have power management keys (e.g., Power key, Sleep key and Wake key); Internet keys to access a web browser or E-mail; and/or multimedia keys, such as volume controls.

Multiple Layouts

It possible to install multiple keyboard layout and switch among them in computer with the help of either operating system or application program. Microsoft Windows^[8], Ubuntu^[9], Linux^[10], Mac^[11] provide support to add keyboard layouts and choose from them.

Layout changing software

Depending on operating systems, various application programs are available to create, add and switch among keyboard layouts. For example, Ukelele for Mac, The Microsoft Keyboard Layout Creator^[12] and open source Avro Keyboard for Windows provide the ability to customize the keyboard layout as desired. Many other similar softwares^[13] are available, some of which are language specific.

Illumination

Keyboards and keypads may be illuminated from inside, especially on equipment for mobile use. Illumination facilitates the use of the keyboard or keypad in dark environments. Some gaming keyboards have lighted keys, to make it easier for gamers to find command keys while playing in a dark room. Some computers may have small LED lights in a few important function keys, to remind users that the function is activated (see photo).

Keys with integrated LED indicator lights

Technology

Key switches

In the first electronic keyboards in the early 1970s, the key switches were individual switches inserted into holes in metal frames. These keyboards cost from 80–120 US dollars and were used in mainframe data terminals. The most popular switch types were reed switches (contacts enclosed in a vacuum in a glass capsule, affected by a magnet mounted on the switch plunger – from Clare-Pendar in Post Falls Idaho, which became part of General Instrument, which used reedswitch capsules made by C.P. Clare Co. in Illinois; and Key Tronic Corporation of Spokane, Washington), Hall-effect switches (using a Hall-effect semiconductor where a current is generated by a passing magnet – from Microswitch in Illinois, which became part of Honeywell), and inductive core switches (again, activated by a magnet – from Cortron, which was part of ITW/Illinois Tool Works). These switches were rated to last for 100 million cycles and had 0.187-inch (4.75 mm) key travel, compared to 0.110 inch (2.79 mm) today.
In the mid 1970's, lower-cost direct-contact key switches were introduced, but their life in switch cycles was much shorter (rated ten million cycles) because they were open to the environment. This became more acceptable, however, for use in computer terminals at the time, which began to see increasingly shorter model lifespans as they advanced.
In 1978, Key Tronic Corporation introduced keyboards with capacitive-based switches, one of the first keyboard technologies to not use self-contained switches. There was simply a sponge pad with a conductive-coated Mylar plastic sheet on the switch plunger, and two half-moon trace patterns on the printed circuit board below. As the key was depressed, the capacitance between the plunger pad and the patterns on the PCB below changed, which was detected by IC's/Integrated Circuits. These keyboards were claimed to have the same reliability as the other "solid-state switch" keyboards such as inductive and Hall-Effect, but competitive with direct-contact keyboards. Prices of $60 for keyboards were achieved and Key Tronic rapidly became the largest independent keyboard manufacturer.
Meanwhile, IBM made their own keyboards, using their own patented technology: Keys on older IBM keyboards were made with a "buckling spring" mechanism, in which a coil spring under the key buckles under pressure from the user's finger, pressing a rubber dome, whose inside is coated with conductive graphite, which connects two leads below, completing a circuit. This produces a clicking sound, and gives physical feedback for the typist indicating that the key has been depressed.^[14]^[15]
The first electronic keyboards had a typewriter key travel distance of 0.187 inches (4.75 mm), keytops were a half-inch (12.7 mm) high, and keyboards were about two inches (5 cm) thick. Over time, less key travel was accepted in the market, finally landing on 0.110 inches (2.79 mm). Coincident with this, Key Tronic was the first company to introduce a keyboard which was only about one inch thick. And now keyboards measure only about a half-inch thick.
Keytops are an important element of keyboards. In the beginning, keyboard keytops had a "dish shape" on top, like typewriters before them. Keyboard key legends must be extremely durable over tens of millions of depressions, since they are subjected to extreme mechanical wear from fingers and fingernails, and subject to hand oils and creams, so engraving and filling key legends with paint, as was done previously for individual switches, was never acceptable. So, for the first electronic keyboards, the key names/legends were produced by two-shot (or double-shot, or two-color) molding, where either the key shell or the inside of the key with the key legend was molded first, and then the other color molded second. But, to save cost, other methods were explored, such as sublimation printing and laser engraving, both methods which could be used to print a whole keyboard at the same time. Initially, sublimation printing, where a special ink is printed onto the keycap surface and the application of heat causes the ink molecules to penetrate and commingle with the plastic modules, had a problem because finger oils caused the molecules to disperse, but then a necessarily very hard clear coating was applied to prevent this. Coincident with sublimation printing, which was first used in high volume by IBM on their keyboards, was the introduction by IBM of single-curved-dish keycaps to facilitate quality printing of key legends by having a consistently-curved surface instead of a dish. But one problem with sublimation or laser printing was that the processes took too long and only dark legends could be printed on light-colored keys. On another note, IBM was unique in using separate shells, or "keycaps", on keytop bases. This might have made their manufacturing of different keyboard layouts more flexible, but the reason for doing this was that the plastic material that needed to be used for sublimation printing was different than standard ABS keytop plastic material.
Three final mechanical technologies brought keyboards to where they are today, driving the cost well under $10:

"Monoblock" keyboard designs were developed where individual switch housings were eliminated and a one-piece "monoblock" housing used instead. This was possible because of molding techniques that could provide very tight tolerances for the switch-plunger holes and guides across the width of the keyboard so that the key plunger-to-housing clearances were not too tight or too loose, either of which could cause the keys to bind.
The use of contact-switch membrane sheets under the monoblock. This technology came from flat-panel switch membranes, where the switch contacts are printed inside of a top and bottom layer, with a spacer layer in between, so that when pressure is applied to the area above, a direct electrical contact is made. The membrane layers can be printed by very-high volume, low-cost "reel-to-reel" printing machines, with each keyboard membrane cut and punched out afterwards.
The use of pad-printed keytops (called "Tampo printed" at the time because Tampo was the most popular equipment manufacturer). Initially sublimation ink was used (see above), but very durable clear-coats are now printed over the key legends to protect them. These coatings are also used to reduce glare, and in many cases have an anti-microbial content added for user protection.^[16]

Plastic materials played a very important part in the development and progress of electronic keyboards. Until "monoblocks" came along, GE's "self-lubricating" Delrin was the only plastic material for keyboard switch plungers that could withstand the beating over tens of millions of cycles of lifetime use. Greasing or oiling switch plungers was undesirable because it would attract dirt over time which would eventually affect the feel and even bind the key switches (although keyboard manufacturers would sometimes sneak this into their keyboards, especially if they could not control the tolerances of the key plungers and housings well enough to have a smooth key depression feel or prevent binding). But Delrin was only available in black and white, and was not suitable for keytops (too soft), so keytops use ABS plastic. However, as plastic molding advanced in maintaining tight tolerances, and as key travel length reduced from 0.187-inch to 0.110-inch (4.75 mm to 2.79 mm), single-part keytop/plungers could be made of ABS, with the keyboard monolocks also made of ABS.

Control processor

Computer keyboards include control circuitry to convert key presses into key codes that the computer's electronics can understand. The key switches are connected via the printed circuit board in an electrical X-Y matrix where a voltage is provided sequentially to the Y lines and, when a key is depressed, detected sequentially by scanning the X lines.
The first computer keyboards were for mainframe computer data terminals and used discrete electronic parts. The first keyboard microprocessor was introduced in 1972 by General Instruments, but keyboards have been using the single-chip 8048 microcontroller variant since it became available in 1978. The keyboard switch matrix is wired to its inputs, it converts the keystrokes to key codes, and, for a detached keyboard, sends the codes down a serial cable (the keyboard cord) to the main processor on the computer motherboard. This serial keyboard cable communication is only bi-directional to the extent that the computer's electronics controls the illumination of the "caps lock", "num lock" and "scroll lock" lights.
One test for whether the computer has crashed is pressing the "caps lock" key. The keyboard sends the key code to the keyboard driver running in the main computer; if the main computer is operating, it commands the light to turn on. All the other indicator lights work in a similar way. The keyboard driver also tracks the shift, alt and control state of the keyboard.
Some lower-quality keyboards have multiple or false key entries due to inadequate electrical designs. These are caused by inadequate keyswitch "debouncing" or inadequate keyswitch matrix layout that don't allow multiple keys to be depressed at the same time, both circumstances which are explained below:
When pressing a keyboard key, the key contacts "bounce" against each other several times for several milliseconds before they settle into firm contact (although this was not true with early "solid-state" keyswitch keyboards that used Hall-effect, inductive, or capacitive keyswitch technologies). When released, they bounce some more until they revert to the uncontacted state. If the computer were watching for each pulse, it would see many keystrokes for what the user thought was just one. To resolve this problem, the processor in a keyboard (or computer) "debounces" the keystrokes, by aggregating them across time to produce one "confirmed" keystroke that (usually) corresponds to what is typically a solid contact.
Some low-quality keyboards also suffer problems with rollover (that is, when multiple keys pressed at the same time, or when keys are pressed so fast that multiple keys are down within the same milliseconds). Early "solid-state" keyswitch keyboards did not have this problem because the keyswitches are electrically isolated from each other, and early "direct-contact" keyswitch keyboards avoided this problem by having isolation diodes for every keyswitch. So, these early keyboards had "n-key" rollover, which means any number of keys can be depressed and the keyboard will still recognize the next key depressed. But when three keys are pressed (electrically closed) at the same time in a "direct contact" keyswitch matrix that doesn't have isolation diodes (diode are not practical with current membrane-switch based keyboards), the keyboard electronics can see a fourth "phantom" key which is the intersection (shorting out) of the X and Y lines of the three keys. Some types of keyboard circuitry will register a maximum number of keys at one time, such as "three-key" rollover maximum, also called "phantom key blocking" or "phantom key lockout", meaning that it will only register three keys and ignore all others until one of the three keys is lifted. This is of course undesirable, especially for fast typing (hitting new keys before the fingers can release previous keys, and undesirable for games (designed for multiple key presses).
As direct-contact membrane keyboards became popular, the available rollover of keys was optimized by analyzing the most common key sequences and placing these keys so that they do not potentially produce phantom keys in the electrical key matrix (for example, simply placing three or four keys that might be depressed simultaneously on the same X or same Y line, so that a phantom key intersection/short cannot happen), so that blocking a third key usually isn't a problem. But lower-quality keyboard designs and unknowledgeable engineers may not know these tricks, and it can still be a problem in games due to wildly different and/or configurable key/command layouts in different games.

Connection types

There are several ways of connecting a keyboard to a system unit (more precisely, to its keyboard controller) using cables, including the standard AT connector commonly found on motherboards, which was eventually replaced by the PS/2 and the USB connection. Prior to the iMac line of systems, Apple used the proprietary Apple Desktop Bus for its keyboard connector.
Wireless keyboards have become popular for their increased user freedom. A wireless keyboard often includes a required combination transmitter and receiver unit that attaches to the computer's keyboard port (see Connection types above). The wireless aspect is achieved either by radio frequency (RF) or by infrared (IR) signals sent and received from both the keyboard and the unit attached to the computer. A wireless keyboard may use an industry standard RF, called Bluetooth. With Bluetooth, the transceiver may be built into the computer. However, a wireless keyboard needs batteries to work and may pose a security problem due to the risk of data "eavesdropping" by hackers. An early example of a consumer wireless keyboard is that of the Olivetti Envision.

Alternative text-entering methods

An on-screen keyboard controlled with the mouse can be used by users with limited mobility.

Optical character recognition (OCR) is preferable to rekeying for converting existing text that is already written down but not in machine-readable format (for example, a Linotype-composed book from the 1940s). In other words, to convert the text from an image to editable text (that is, a string of character codes), a person could re-type it, or a computer could look at the image and deduce what each character is. OCR technology has already reached an impressive state (for example, Google Book Search) and promises more for the future.
Speech recognition converts speech into machine-readable text (that is, a string of character codes). The technology has already reached an impressive state and is already implemented in various software products. For certain uses (e.g., transcription of medical or legal dictation; journalism; writing essays or novels) it is starting to replace the keyboard; however, it does not threaten to replace keyboards entirely anytime soon. It can, however, interpret commands (for example, "close window" or "undo that") in addition to text. Therefore, it has theoretical potential to replace keyboards entirely (whereas OCR replaces them only for a certain kind of task).
Pointing devices can be used to enter text or characters in contexts where using a physical keyboard would be inappropriate or impossible. These accessories typically present characters on a display, in a layout that provides fast access to the more frequently used characters or character combinations. Popular examples of this kind of input are Graffiti, Dasher and on-screen virtual keyboards.

Other issues

Keystroke hacking

Keystroke logging (often called keylogging) is a method of capturing and recording user keystrokes. While it is used legally to measure employee productivity on certain clerical tasks, or by law enforcement agencies to find out about illegal activities, it is also used by hackers for various illegal or malicious acts. Hackers use keyloggers as a means to obtain passwords or encryption keys and thus bypass other security measures.
Keystroke logging can be achieved by both hardware and software means. Hardware key loggers are attached to the keyboard cable or installed inside standard keyboards. Software keyloggers work on the target computer’s operating system and gain unauthorized access to the hardware, hook into the keyboard with functions provided by the OS, or use remote access software to transmit recorded data out of the target computer to a remote location. Some hackers also use wireless keylogger sniffers to collect packets of data being transferred from a wireless keyboard and its receiver, and then they crack the encryption key being used to secure wireless communications between the two devices.
Anti-spyware applications are able to detect many keyloggers and cleanse them. Responsible vendors of monitoring software support detection by anti-spyware programs, thus preventing abuse of the software. Enabling a firewall does not stop keyloggers per se, but can possibly prevent transmission of the logged material over the net if properly configured. Network monitors (also known as reverse-firewalls) can be used to alert the user whenever an application attempts to make a network connection. This gives the user the chance to prevent the keylogger from "phoning home" with his or her typed information. Automatic form-filling programs can prevent keylogging entirely by not using the keyboard at all. Most keyloggers can be fooled by alternating between typing the login credentials and typing characters somewhere else in the focus window.^[17]

Wireless keystroke hacking

Also known as remote keylogging or wireless keylogging.
In their research “Compromising Electromagnetic Emanations of Wired Keyboard”^[18] Vuagnoux and Pasini have provided evidence that modern keyboards radiate compromising electromagnetic emanations. The four techniques presented in their paper prove that these basic devices are generally not sufficiently protected against compromising emanations. Additionally, they showed that these emanations can be captured with relatively inexpensive equipment and keystrokes are recovered^[19] not only in the semi-anechoic chamber but in practical environments as well (e.g office). The consequences of these attacks are that compromising electromagnetic emanations of keyboards still represent a security risk. PS/2, USB, laptop and wireless keyboards are vulnerable. Moreover, there is no software patch to avoid these attacks. Hardware has to be replaced in order to obtain safe devices. Due to cost pressure in the design and lack of knowledge, manufacturers do not systematically protect keyboards. Even in the practical space of an office with multiple keyboards, Vuagnoux and Pasini were able to deduce a specific fingerprint for every keyboard. When multiple keyboards are radiating at the same time, they are able to identify and differentiate them.

Physical injury

Proper ergonomic design of computer keyboard desks is necessary to prevent repetitive strain injuries, which can develop over time and can lead to long-term disability.^[20]

The use of any keyboard may cause serious injury (that is, carpal tunnel syndrome or other repetitive strain injury) to hands, wrists, arms, neck or back. The risks of injuries can be reduced by taking frequent short breaks to get up and walk around a couple of times every hour. As well, users should vary tasks throughout the day, to avoid overuse of the hands and wrists. When inputting at the keyboard, a person should keep the shoulders relaxed with the elbows at the side, with the keyboard and mouse positioned so that reaching is not necessary. The chair height and keyboard tray should be adjusted so that the wrists are straight, and the wrists should not be rested on sharp table edges. Wrist or palm rests should not be used while typing.
Some adaptive technology ranging from special keyboards, mouse replacements and pen tablet interfaces to speech recognition software can reduce the risk of injury. Pause software reminds the user to pause frequently. Switching to a much more ergonomic mouse, such as a vertical mouse or joystick mouse may provide relief. Switching from using a mouse to using a stylus pen with graphic tablet or a trackpad can lessen the repetitive strain on the arms and hands.

KEYBOARD HACK

2011-03-02T09:50:00.000-08:00

Happy Hacking Keyboard

The Happy Hacking Keyboard is a small computer keyboard produced by PFU Limited of Japan. The current models in production are the Happy Hacking Keyboard Professional 2,^[1] Professional JP,^[2] and the Happy Hacking Keyboard Lite 2.

A white Happy Hacking Keyboard Professional 2 with blank keys.

1 Common Features

Common Features

Happy Hacking Keyboards lack a numeric keypad, and keys outside the typewriter key area are mainly accessible through the Fn key. The keys are arranged in a layout resembling the Sun Type 3 keyboard. Specifically:

The control key is found where most keyboards place the caps lock. This is the only control key on the keyboard.
The esc key is located to the left of the 1 key; the tilde key normally found there is at the right end of the same row.
The delete key is located directly above the enter key; the key normally found there is the second rightmost key on the row above it. Furthermore, this is an actual delete key, not a historically named backspace. Backspace is accessible through Fn+Delete.
The windows/command key is located between the space bar and the alt keys, and is represented by ◇.

On the far side of the keyboard there are DIP switches. These may be used to^[3]

Turn the delete key into a backspace. Fn+Delete remains backspace, and Fn + top-right key remains delete.
Swap the alt and meta keys.
Enable/disable downstream USB ports on USB models.

Features by Model

Model Name	Model #	Color	Switch Type	Interface	Blank Keytops	Introduced	EOL	Other Features
Happy Hacking Keyboard	PD-KB02	White	Membrane	PS/2, Sun, ADB	No	Dec 20, 1996	Dec 10, 2006^[4]	Buzzer (Sun), Power supply switch (Sun/Mac)
Happy Hacking Keyboard	PD-KB02N	White		PS/2, Sun, ADB		Dec 20, 1996	Dec 10, 2006^[4]	Buzzer (Sun), Power supply switch (Sun/Mac)
Happy Hacking Keyboard Lite	PD-KB100W	White		PS/2		Jun 7, 1999^[5]	Unknown	Was also available in black and white non-labeled versions^[6]
Happy Hacking Keyboard Lite 2	PD-KB200W/P	White				Mar 15, 2001^[7]	Dec 19, 2008	Arrow keys, 2-port USB hub. Available in Japanese and English layouts.
	PD-KB200B/P	Black					Dec 19, 2008
	PD-KB200W/U	White		USB
	PD-KB200B/U	Black
	PD-KB210W/U	White
	PD-KB210B/U	Black
	PD-KB220W/U	White
	PD-KB220B/U	Black
	PD-KB220MKW	White						Mac version, has command and option keys in addition to the other Lite 2 features.^[8]
	PD-KB200MKB	Black
	PD-KB200MA	White
	PD-KB220MA	White
Happy Hacking Keyboard Professional	PD-KB300	White	Capacitive^[9]			Apr 24, 2003	Dec 10, 2006^[4]
	PD-KB300B	Charcoal Gray
	PD-KB300NL	White			Yes
	PD-KB300BN	Charcoal Gray			Yes
Happy Hacking Keyboard Professional 2	PD-KB400W	White			No	Mar 24, 2006^[10]		2-port USB hub
	PD-KB400B	Charcoal Gray			No
	PD-KB400WN	White			Yes
	PD-KB400BN	Charcoal Gray			Yes
Happy Hacking Keyboard Professional JP	PD-KB420W	White			No	Nov 10, 2008		HHKB Professional 2 with Japanese layout and arrow keys
Happy Hacking Keyboard Professional JP	PD-KB420B	Charcoal Gray			No	Nov 10, 2008		HHKB Professional 2 with Japanese layout and arrow keys
Happy Hacking Keyboard Professional HG^[11]	PD-KB500W	White			No	Oct 12, 2006		Special 10-year anniversary models^[12]
	PD-KB500B	Black			No
	PD-KB500WN	White			Yes
	PD-KB500BN	Black
Happy Hacking Keyboard Professional HG JAPAN^[13]	PD-KB500J	Wajima-style lacquer

HACKER

2011-03-02T09:40:00.000-08:00

In common usage, a hacker is a stereotypical person who breaks into computers and computer networks, either for profit or motivated by the challenge.^[1] The subculture that has evolved around hackers is often referred to as the computer underground but is now an open community.^[2]

Other definitions of the word hacker exist that are not related to computer security. They are subject to the long standing hacker definition controversy about the true meaning of hacker. In this controversy, the term hacker is reclaimed by computer programmers who argue that someone breaking into computers is better called cracker,^[3] not making a difference between computer criminals ("black hats") and computer security experts ("white hats"). Some white hat hackers claim that they also deserve the title hacker, and that only black hats should be called crackers. None of this controversy has gained any relevance in mainstream media, TV and movies, however.^{[citation needed]}

1 History
2 Artifacts and customs
- 2.1 Hacker groups and conventions
3 Hacker attitudes
4 Attacks
- 4.1 Security exploits
- 4.2 Techniques
5 Notable intruders and criminal hackers
6 Notable security hackers
7 Hacking and the media
- 7.1 Hacker magazines
- 7.2 Hackers in fiction
- 7.3 Non-fiction books
- 7.4 Fiction books
8 See also
9 References
10 Related literature
11 External links

History

Further information: Timeline of computer security hacker history

In today's society understanding the term "hacker" is complicated because it has many different definitions. The term can be traced back to MIT (Massachusetts Institute Technology). MIT was the first institution to offer a course in computer programming and computer science and it is here in 1960 where a group of MIT students taking a lab on artificial intelligence first coined this word. These students called themselves hackers because they were able to take programs and have them perform actions not intended for that program. “The term was developed on the basis of a practical joke and feeling of excitement because the team member would “hack away” at the keyboard hours at a time.” (Moore R., 2006).^[4]

Hacking developed alongside phone phreaking, a term referred to exploration of the phone network without authorization, and there has often been overlap between both technology and participants.^{[citation needed]} The first recorded^{[citation needed]} hack was accomplished by Joe Engressia also known as The Whistler. Engressia is known as the grandfather of phreaking. His hacking technique was that he could perfectly whistle a tone into a phone and make free call.^[5] Bruce Sterling traces part of the roots of the computer underground to the Yippies, a 1960s counterculture movement which published the Technological Assistance Program^[6] Other sources of early 1970s hacker culture can be traced towards more beneficial forms of hacking, including MIT labs or the Homebrew Computer Club, which later resulted in such things as early personal computers or the open source movement. (TAP) newsletter.

[edit] Artifacts and customs

The computer underground^[1] is heavily dependent on technology. It has produced its own slang and various forms of unusual alphabet use, for example 1337speak. Writing programs and performing other activities to support these views is referred to as hacktivism. Some go as far as seeing illegal cracking ethically justified for this goal; a common form is website defacement. The computer underground is frequently compared to the Wild West.^[7] It is common among hackers to use aliases for the purpose of concealing identity, rather than revealing their real names.

Hacker groups and conventions

Main articles: Hacker conference and Hacker group

The computer underground is supported by regular real-world gatherings called hacker conventions or "hacker cons". These drawn many people every year including SummerCon (Summer), DEF CON, HoHoCon (Christmas), ShmooCon (February), BlackHat, Hacker Halted, and H.O.P.E..^{[citation needed]}. In the early 1980s Hacker Groups became popular, Hacker groups provided access to information and resources, and a place to learn from other members. Hackers could also gain credibility by being affiliated with an elite group.^[8]

Hacker attitudes

Several subgroups of the computer underground with different attitudes and aims use different terms to demarcate themselves from each other, or try to exclude some specific group with which they do not agree. Eric S. Raymond (author of The New Hacker's Dictionary) advocates that members of the computer underground should be called crackers. Yet, those people see themselves as hackers and even try to include the views of Raymond in what they see as one wider hacker culture, a view harshly rejected by Raymond himself. Instead of a hacker/cracker dichotomy, they give more emphasis to a spectrum of different categories, such as white hat, grey hat, black hat and script kiddie. In contrast to Raymond, they usually reserve the term cracker. According to (Clifford R.D. 2006) a cracker or cracking is to "gain unauthorized access to a computer in order to commit another crime such as destroying information contained in that system".^[9] These subgroups may also be defined by the legal status of their activities.^[10]

White hat: A white hat hacker breaks security for non-malicious reasons, for instance testing their own security system. This classification also includes individuals who perform penetration tests and vulnerability assessments within a contractual agreement. Often, this type of 'white hat' hacker is called an ethical hacker. The International Council of Electronic Commerce Consultants, also known as the EC-Council^[10] has developed certifications, courseware, classes, and online training covering the diverse arena of Ethical Hacking.
Black hat: A black hat hacker, sometimes called a cracker, is someone who breaks computer security without authorization or uses technology (usually a computer, phone system or network) for malicious reasons such as vandalism, credit card fraud, identity theft, piracy, or other types of illegal activity.^[10]^[11]
Grey hat: A grey hat hacker is a combination of a Black Hat and a White Hat Hacker. A Grey Hat Hacker may surf the internet and hack into a computer system for the sole purpose of notifying the administrator that their system has been hacked, for example. Then they may offer to repair their system for a small fee.^[4]
Elite hacker: A social status among hackers, elite is used to describe the most skilled. Newly discovered exploits groups such as Masters of Deception conferred a kind of credibility on their members.^[12]^:86,90,117 Elite (e.g. 31337) gives the term leet speak its name. will circulate among these hackers. Elite
Script kiddie: A script kiddie is a non-expert who breaks into computer systems by using pre-packaged automated tools written by others, usually with little understanding of the underlying concept—hence the term script (i.e. a prearranged plan or set of activities) kiddie (i.e. kid, child—an individual lacking knowledge and experience, immature).^[11]
Neophyte: A neophyte, "n00b", or "newbie" is someone who is new to hacking or phreaking and has almost no knowledge or experience of the workings of technology, and hacking.^[4]
Blue hat: A blue hat hacker is someone outside computer security consulting firms who is used to bug test a system prior to its launch, looking for exploits so they can be closed. Microsoft also uses the term BlueHat to represent a series of security briefing events.^[13]^[14]^[15]
Hacktivist: A hacktivist is a hacker who utilizes technology to announce a social, ideological, religious, or political message. In general, most hacktivism involves website defacement or denial-of-service attacks. In more extreme cases, hacktivism is used as tool for cyberterrorism.

Attacks

Main article: Computer insecurity

Computer security
Secure operating systems
Security architecture
Security by design
Secure coding
Computer insecurity
Vulnerability	Social engineering Eavesdropping
Exploits	Trojans Viruses and worms Denial of service
Payloads	Backdoors Rootkits Keyloggers
v · d · e

A typical approach in an attack on Internet-connected system is:

Network enumeration: Discovering information about the intended target.
Vulnerability analysis: Identifying potential ways of attack.
Exploitation: Attempting to compromise the system by employing the vulnerabilities found through the vulnerability analysis.^[16]

In order to do so, there are several recurring tools of the trade and techniques used by computer criminals and security experts.

[edit] Security exploits

Main article: Exploit (computer security)

A security exploit is a prepared application that takes advantage of a known weakness. Common examples of security exploits are SQL injection, Cross Site Scripting and Cross Site Request Forgery which abuse security holes that may result from substandard programming practice. Other exploits would be able to be used through FTP, HTTP, PHP, SSH, Telnet and some web-pages. These are very common in website/domain hacking.

Techniques

Vulnerability scanner: A vulnerability scanner is a tool used to quickly check computers on a network for known weaknesses. Hackers also commonly use port scanners. These check to see which ports on a specified computer are "open" or available to access the computer, and sometimes will detect what program or service is listening on that port, and its version number. (Note that firewalls defend computers from intruders by limiting access to ports/machines both inbound and outbound, but can still be circumvented.)
Password cracking: Password cracking is the process of recovering passwords from data that has been stored in or transmitted by a computer system. A common approach is to repeatedly try guesses for the password.
Packet sniffer: A packet sniffer is an application that captures data packets, which can be used to capture passwords and other data in transit over the network.
Spoofing attack: A spoofing attack involves one program, system, or website successfully masquerading as another by falsifying data and thereby being treated as a trusted system by a user or another program. The purpose of this is usually to fool programs, systems, or users into revealing confidential information, such as user names and passwords, to the attacker.
Rootkit: A rootkit is designed to conceal the compromise of a computer's security, and can represent any of a set of programs which work to subvert control of an operating system from its legitimate operators. Usually, a rootkit will obscure its installation and attempt to prevent its removal through a subversion of standard system security. Rootkits may include replacements for system binaries so that it becomes impossible for the legitimate user to detect the presence of the intruder on the system by looking at process tables.
Social engineering: Social engineering is the art of getting persons to reveal sensitive information about a system. This is usually done by impersonating someone or by convincing people to believe you have permissions to obtain such information.
Trojan horses: A Trojan horse is a program which seems to be doing one thing, but is actually doing another. A trojan horse can be used to set up a back door in a computer system such that the intruder can gain access later. (The name refers to the horse from the Trojan War, with conceptually similar function of deceiving defenders into bringing an intruder inside.)
Viruses: A virus is a self-replicating program that spreads by inserting copies of itself into other executable code or documents. Therefore, a computer virus behaves in a way similar to a biological virus, which spreads by inserting itself into living cells.

While some are harmless or mere hoaxes most computer viruses are considered malicious.
Worms: Like a virus, a worm is also a self-replicating program. A worm differs from a virus in that it propagates through computer networks without user intervention. Unlike a virus, it does not need to attach itself to an existing program. Many people conflate the terms "virus" and "worm", using them both to describe any self-propagating program.
Key loggers: A key logger is a tool designed to record ('log') every keystroke on an affected machine for later retrieval. Its purpose is usually to allow the user of this tool to gain access to confidential information typed on the affected machine, such as a user's password or other private data. Some key loggers uses virus-, trojan-, and rootkit-like methods to remain active and hidden. However, some key loggers are used in legitimate ways and sometimes to even enhance computer security. As an example, a business might have a key logger on a computer used at a point of sale and data collected by the key logger could be used for catching employee fraud.

Notable intruders and criminal hackers

Main article: List of convicted computer criminals

Notable security hackers

Main article: List of hackers

Kevin Mitnick is a computer security consultant and author, formerly the most wanted computer criminal in United States history.^[17]
Eric Corley (also known as Emmanuel Goldstein) is the long standing publisher of 2600: The Hacker Quarterly. He is also the founder of the H.O.P.E. conferences. He has been part of the hacker community since the late '70s.
Gordon Lyon, known by the handle Fyodor, authored the Nmap Security Scanner as well as many network security books and web sites. He is a founding member of the Honeynet Project and Vice President of Computer Professionals for Social Responsibility.
Solar Designer is the pseudonym of the founder of the Openwall Project.
Michał Zalewski (lcamtuf) is a prominent security researcher.
Gary McKinnon is a British hacker facing extradition to the United States to face charges of perpetrating what has been described as the "biggest military computer hack of all time".^[18]

Hacking and the media

This section is in a list format that may be better presented using prose. You can help by converting this section to prose, if appropriate. Editing help is available. (August 2008)

Hacker magazines

Main category: Hacker magazines.

The most notable hacker-oriented magazine publications are Phrack, Hakin9 and 2600: The Hacker Quarterly. While the information contained in hacker magazines and ezines was often outdated, they improved the reputations of those who contributed by documenting their successes.^[8]

Hackers in fiction

See also: List of fictional hackers

Hackers often show an interest in fictional cyberpunk and cyberculture literature and movies. Absorption of fictional pseudonyms, symbols, values, and metaphors from these fictional works is very common.^{[citation needed]}

Books portraying hackers:

The cyberpunk novels of William Gibson — especially the Sprawl Trilogy — are very popular with hackers.^[19]
Merlin, the protagonist of the second series in The Chronicles of Amber by Roger Zelazny is a young immmortal hacker-mage prince who has the ability to traverse shadow dimensions.
Hackers (short stories)
Snow Crash
Helba from the .hack manga and anime series.
Little Brother by Cory Doctorow
Rice Tea by Julien McArdle
Lisbeth Salander in The Girl with the Dragon Tattoo by Stieg Larsson

Films also portray hackers:

Cypher
Tron
WarGames
The Matrix series
Hackers
Swordfish

Pirates of silicon valley (related to hacker like Steve Jobs, not crackers)

Non-fiction books

Hacking: The Art of Exploitation, Second Edition by Jon Erickson
The Hacker Crackdown
The Art of Intrusion by Kevin D. Mitnick
The Art of Deception by Kevin D. Mitnick
Takedown
The Hacker's Handbook
The Cuckoo's Egg by Clifford Stoll
Underground by Suelette Dreyfus

COMPUTER HACKING

2011-03-02T09:36:00.001-08:00

Hacking may refer to:

Computer hacking, including the following types of activity:
- Hacker (programmer subculture), activity within the computer programmer subculture
- Hacker (hobbyist), to heavily modify the software or hardware of one's own computer system
- Hacker (computer security), to access computer networks, legally or otherwise
- Computer crime
Illegal taxicab operation
Pleasure riding, horseback riding for purely recreational purposes
The act of stealing jokes
Hacking, an area within Hietzing, a municipal district of Vienna, Austria
Ian Hacking, Canadian philosopher of science

TYPES OF COMPUTER

2011-03-02T09:34:00.000-08:00

Microcomputers (Personal computers)

Microcomputers are the most common type of computers in existence today, whether in a workplace, at school or on the desk at home. The term “microcomputer” was introduced with the advent of single chip microprocessors. The term “microcomputer” itself is now practically an anachronism.

These computers include:

Desktop computers – A case and a display, put under and on a desk.
In-car computers (“carputers”) – Built into a car, for entertainment, navigation, etc.

A separate class is that of mobile devices:

Laptops, notebook computers and Palmtop computers – Portable and all in one case. Varying sizes, but other than smartbooks expected to be “full” computers without limitations.
Tablet PC – Like laptops, but with only a touch-screen instead of a physical keyboard.
Smartphones, smartbooks and PDAs (personal digital assistants) – Small handheld computers with limited hardware.
Programmable calculator– Like small handhelds, but specialised on mathematical work.
Game consoles – Fixed computers specialized for entertainment purposes (computer games).
Handheld game consoles – The same as game consoles, but small and portable.

Minicomputers (Midrange computers)

A minicomputer (colloquially, mini) is a class of multi-user computers that lies in the middle range of the computing spectrum, in between the smallest multi-user systems (mainframe computers) and the largest single-user systems (microcomputers or personal computers). The contemporary term for this class of system is midrange computer, such as the higher-end SPARC, POWER and Itanium -based systems from Sun Microsystems, IBM and Hewlett-Packard.

Mainframe Computers

The term mainframe computer was created to distinguish the traditional, large, institutional computer intended to service multiple users from the smaller, single user machines. These computers are capable of handling and processing very large amounts of data quickly. Mainframe computers are used in large institutions such as government, banks and large corporations. These institutions were early adopters of computer use, long before personal computers were available to individuals. "Mainframe" often refers to computers compatible with the computer architectures established in the 1960s. Thus, the origin of the architecture also affects the classification, not just processing power.

Mainframes are measured in millions of instructions per second or MIPS. An example of integer operation is moving data around in memory or I/O devices. A more useful industrial benchmark is transaction processing as defined by the Transaction Processing Performance Council. Mainframes are built to be reliable for transaction processing as it is commonly understood in the business world: a commercial exchange of goods, services, or money. A typical transaction, as defined by the Transaction Processing Performance Council, would include the updating to a database system for such things as inventory control (goods), airline reservations (services), or banking (money). A transaction could refer to a set of operations including disk read/writes, operating system calls, or some form of data transfer from one subsystem to another.

Supercomputer

A supercomputer is focused on performing tasks involving intense numerical calculations such as weather forecasting, fluid dynamics, nuclear simulations, theoretical astrophysics, and complex scientific computations. A supercomputer is a computer that is at the frontline of current processing capacity, particularly speed of calculation. The term supercomputer itself is rather fluid, and the speed of today's supercomputers tends to become typical of tomorrow's ordinary computer. Supercomputer processing speeds are measured in floating point operations per second or FLOPS. Example of floating point operation is the calculation of mathematical equations in real numbers. In terms of computational capability, memory size and speed, I/O technology, and topological issues such as bandwidth and latency, Supercomputers are the most powerful. Supercomputers are very expensive and not cost-effective just to perform batch or transaction processing. Transaction processing is handled by less powerful computer such as server computer or mainframe.

Classes by function

Servers

Server usually refers to a computer that is dedicated to providing a service. For example, a computer dedicated to a database may be called a "database server". "File servers" manage a large collection of computer files. "Web servers" process web pages and web applications. Many smaller servers are actually personal computers that have been dedicated to providing services for other computers.

Workstations

Workstations are computers that are intended to serve one user and may contain special hardware enhancements not found on a personal computer.

Information appliances

Information appliances are computers specially designed to perform a specific user-friendly function —such as playing music, photography, or editing text. The term is most commonly applied to mobile devices, though there are also portable and desktop devices of this class.

Embedded computers

Embedded computers are computers that are a part of a machine or device. Embedded computers generally execute a program that is stored in non-volatile memory and is only intended to operate a specific machine or device. Embedded computers are very common. Embedded computers are typically required to operate continuously without being reset or rebooted, and once employed in their task the software usually cannot be modified. An automobile may contain a number of embedded computers; however, a washing machine and a DVD player would contain only one. The central processing units (CPUs) used in embedded computers are often sufficient only for the computational requirements of the specific application and may be slower and cheaper than CPUs found in a personal computer.

HISTORY OF COMPUTER

2011-03-02T09:18:00.000-08:00

The first computers were people! That is, electronic computers (and the earlier mechanical computers) were given this name because they performed the work that had previously been assigned to people. "Computer" was originally a job title: it was used to describe those human beings (predominantly women) whose job it was to perform the repetitive calculations required to compute such things as navigational tables, tide charts, and planetary positions for astronomical almanacs. Imagine you had a job where hour after hour, day after day, you were to do nothing but compute multiplications. Boredom would quickly set in, leading to carelessness, leading to mistakes. And even on your best days you wouldn't be producing answers very fast. Therefore, inventors have been searching for hundreds of years for a way to mechanize (that is, find a mechanism that can perform) this task.

This picture shows what were known as "counting tables" [photo courtesy IBM]

A typical computer operation back when computers were people.

The abacus was an early aid for mathematical computations. Its only value is that it aids the memory of the human performing the calculation. A skilled abacus operator can work on addition and subtraction problems at the speed of a person equipped with a hand calculator (multiplication and division are slower). The abacus is often wrongly attributed to China. In fact, the oldest surviving abacus was used in 300 B.C. by the Babylonians. The abacus is still in use today, principally in the far east. A modern abacus consists of rings that slide over rods, but the older one pictured below dates from the time when pebbles were used for counting (the word "calculus" comes from the Latin word for pebble).

A very old abacus

A more modern abacus. Note how the abacus is really just a representation of the human fingers: the 5 lower rings on each rod represent the 5 fingers and the 2 upper rings represent the 2 hands.

In 1617 an eccentric (some say mad) Scotsman named John Napier invented logarithms, which are a technology that allows multiplication to be performed via addition. The magic ingredient is the logarithm of each operand, which was originally obtained from a printed table. But Napier also invented an alternative to tables, where the logarithm values were carved on ivory sticks which are now called Napier's Bones.

An original set of Napier's Bones [photo courtesy IBM]

A more modern set of Napier's Bones

Napier's invention led directly to the slide rule, first built in England in 1632 and still in use in the 1960's by the NASA engineers of the Mercury, Gemini, and Apollo programs which landed men on the moon.

A slide rule

Leonardo da Vinci (1452-1519) made drawings of gear-driven calculating machines but apparently never built any.

A Leonardo da Vinci drawing showing gears arranged for computing

The first gear-driven calculating machine to actually be built was probably the calculating clock, so named by its inventor, the German professor Wilhelm Schickard in 1623. This device got little publicity because Schickard died soon afterward in the bubonic plague.

Schickard's Calculating Clock

In 1642 Blaise Pascal, at age 19, invented the Pascaline as an aid for his father who was a tax collector. Pascal built 50 of this gear-driven one-function calculator (it could only add) but couldn't sell many because of their exorbitant cost and because they really weren't that accurate (at that time it was not possible to fabricate gears with the required precision). Up until the present age when car dashboards went digital, the odometer portion of a car's speedometer used the very same mechanism as the Pascaline to increment the next wheel after each full revolution of the prior wheel. Pascal was a child prodigy. At the age of 12, he was discovered doing his version of Euclid's thirty-second proposition on the kitchen floor. Pascal went on to invent probability theory, the hydraulic press, and the syringe. Shown below is an 8 digit version of the Pascaline, and two views of a 6 digit version:

COMPUTER SYSTEMS

welcome,,,

HACKING TIPS

Access Free Airtel GPRS Using TeaShark Browser

Parallel ATA

Parallel ATA

Contents

History and terminology

IDE and ATA-1

Second ATA interface

EIDE and ATA-2

ATAPI

UDMA and ATA-4

Current terminology

Drive size limitations

Obsolescence

Parallel ATA interface

Differences between connectors on 80-conductor cables

Multiple devices on a cable

Cable select

Master and slave clarification

LINUX UBUNTU OPERATING SYSTEM

Ubuntu (operating system)

Contents

History and development process

Features

System requirements

Installation

Package classification and support

Availability of third-party software

Variants

Development

Reception

Local Communities (LoCos)

Vendor support

KEYBOARD

Computer keyboard

Contents

Keyboard types

Standard

Laptop-size

Thumb-sized

Non-standard layout and special-use types

Chorded

Software

foldable

Projection/laser

Optical keyboard technology

Layout

Alphabetic

Key types

Alphanumeric

Modifiers

Navigation and typing modes

System commands

Miscellaneous

Multiple Layouts

Layout changing software

Illumination

Technology

Key switches

Control processor

Connection types

Alternative text-entering methods

Other issues

Keystroke hacking

Wireless keystroke hacking

Physical injury

KEYBOARD HACK

Happy Hacking Keyboard

Contents

Common Features

Features by Model

HACKER

Contents

History

[edit] Artifacts and customs

Hacker groups and conventions

Hacker attitudes

Attacks