Computer Information

Learn Web Hosting

noreply@blogger.com (IT Consultant) — Tue, 05 Nov 2013 19:56:00 +0000


Web Hosting

You have your new business all established now and you're ready to take the next step and set up a website to tell the online world that you are here and you have something to offer. You found a catchy domain name to call your own , and now ... What to do? Well, the answer is that you need to find web hosting for the site you are going to build. So what does that mean and how do you know what type of web hosting you need ? First let's start with the basics .

Everything is web hosting anyway?

In simple terms , web hosting is renting space on a web server. A website is not just a domain name , it is a collection of files linked together by HTML code to display text and graphics on a computer. For everyone to see this collection of files you 've created, it must be installed on a computer somewhere that has access to the internet. Not just any computer will do, of course . A web server is configured with a special computer program that allows it to receive requests from the internet for the website files it has stored on it and to send those files over the Internet to the computer applicant can show . It looks much like a waiter in a restaurant taking your order and bringing the food you ask the kitchen , hence the name "server" .

To ensure that your files can be accessed by Internet users worldwide , a web server provides other important services as well . First and foremost is the ability to create email addresses based on your domain name and to send and receive emails with them. The Web server also has different types installed on that allow your website to run software programs , create and manage databases , video display , and many other features that you might find useful . Almost any type of computer can function as a web server, but the software is on it making a server.

When you purchase hosting , the monthly fee you pay goes to the maintenance and continuous upgrading of hardware and server software , the cost of maintaining online 24 hours a day , 7 days a week in a secure data center with a powerful and fast internet connection, and pay for the expertise of the people who do all the work . It is quite possible to transform your own home or office computer into a web server if you really want to do , but in most cases it is much cheaper to pay someone else dedicated to provide this service more reliable way is to try to do it yourself .

What types of web hosting are they?

Shared Hosting - Most websites are not huge affairs with hundreds of pages and thousands of files and graphics, and they are targeted to a specific audience , so they will not get as many visitors as the large general sites like Yahoo! that cater to everyone who uses the Internet . As such , the average website therefore will not require all the resources of an entire web server to run . Web servers are designed to be able to manage dozens or hundreds of sites at once because they are powerful machines .

Shared hosting is simply the concept of hosting more than one website on a particular server. More than 95 % of all websites on the Internet are running in a shared hosting environment. Because server resources can be distributed among the clients hosted on it , so can the costs of operating the server, and the universally shared is cheaper than any other type accommodation. Shared hosting packages are generally designed so that each client is assigned a certain amount of each resource , with different payment levels representing different amounts of resources such as disk space, bandwidth , email addresses , and so on . Shared hosting is also known as virtual hosting.

Dedicated Hosting - If you have a large powerful website that attracts many visitors and tend to monopolize the resources , then you may want to have a web server all to yourself . Some companies also prefer the added security of not having to share the server with anyone else who could do something accidentally or intentionally crashing. Rent use of an entire server is known as dedicated hosting. The web hosting company still owns the machine and the responsibility for maintenance of hardware and software web hosting , but you have more control over the configuration and use of the server. There is also such a thing as semi-dedicated hosting , in which a web server is divided into only a very small number of customers, such as 2-4 , with solid partitions between each to prevent them from interfering with the other. Since the hosting company is still responsible for the maintenance of the server, this type of hosting is also known as managed hosting . For obvious reasons , dedicated hosting always costs more than shared hosting .

Server Co -Location - If you really want complete control over all aspects of your Web server, you might very well choose to buy one and maintain it yourself if you have sufficient knowledge . However , chances are that you do not have the means to keep your server completely safe from power outages, roof leaks , thieves, unwary employees and other risks and keep on Internet broadband fast at any time. You need a data center to provide these services for you. Co -location is the rental of physical security, continuous electrical power and a fast and reliable Internet connection to a server you have. The data center is not responsible for any hardware or software of a collocated server , you are servicing. This can be a cheaper alternative to dedicated hosting if you have the expertise and time to turn yourself a necessary alternative web server .

Some hosts offer UNIX hosting and Windows hosting. What is the difference ?

The terms UNIX hosting and Windows hosting refer to the operating system ( OS) running on the server. Of course the operating system is the software that allows the computer to operate and manage all other hardware and software that are installed . Chances are good that you are reading this on a computer running a version of Windows operating system, the world's most popular operating system for personal computers and business . Other operating systems are growing in popularity of Macintosh and various Linux versions . However, the operating system you use on your computer is not relevant to the type of accommodation you choose. Here are some key features of UNIX and Windows :

Unix Hosting

Most Web servers in the world today run on one of the many variants of UNIX . The UNIX operating system was originally developed by universities for servers and networks, and many different versions have been written by programmers around the world under the open- source protocol , which means that the code of the operating system is openly available for programmers to customize and make improvements. Linux and BSD are the most popular forms of UNIX and come in many varieties, such as Red Hat Linux, Debian, SuSE , and FreeBSD. Most of these different versions (and much of the software that runs on them ) can be obtained for free , making UNIX hosting cheaper for a web host that other operating systems and allows them to offer price lower. UNIX platforms hosting are generally considered stable, secure , fast and powerful . Most web programming applications can be performed by software that is available for UNIX platform. "UNIX hosting" has become a generic term for any platform that is derived from the original UNIX.

Windows hosting

Microsoft has developed its own operating system for servers as a special version of its Windows operating system , Windows Server 2003. It is a commercial product that requires the operator to purchase a license , which increases the cost of running the host and usually results in higher hosting prices. Windows is designed to be user friendly , but it is generally considered to be less powerful and secure than UNIX for operating in a network environment. ASP , ASP.NET and ColdFusion are scripting languages that can not be run on a Windows server , as well as programs for Microsoft Access and Microsoft SQL Server databases. These are popular for certain web programming applications , and if you plan to use to build your site , you 'll need to find a Windows host.

What are some of the words I need to know when I choose a web host ?

Disk space or storage - Because your website is a collection of files available on the Internet for viewing, they must be stored somewhere for retrieval and take up space . Each server has a limited amount of memory on the hard drive to divide and provide hosting customers. Typically , this space is divided into different levels of packages so that the more you pay , the more space you are allowed to store images , web pages , videos and any other files that you want on the hard drive the web server. If your site gets larger than the space you have given, you will need to buy more disk space from the host.

Bandwidth or Data Transfer - Whenever you visit a website and view a page , you can transfer a copy of the files that make up this page on the Internet from the web server on your computer. If the page you are viewing consists of an HTML file that is 3KB in size and three pictures of 47KB , 100KB and 250KB , then you just used 400KB of bandwidth or data transfer , because c ' is the total amount of data that you have downloaded from the web server to view this page. Bandwidth is a commodity like disk space that the host has to buy his Internet service provider , so it is too divided and delivered to customers in specific quantities. Amounts of bandwidth are usually measured in gigabytes ( GB) , because if only one copy of your files must be stored on the server, thousands, even millions of copies can be downloaded for consultation. If your site is viewed times the amount of bandwidth you are allowed can manage your site can be disabled until the next billing period starts , or you can simply be billed for the excess amount used , according to the policies your home . You can always buy more bandwidth that increases your site traffic web.

Uptime - In an ideal world, every Web server is operational and offer your web pages in the world 24 hours a day , 7 days a week , forever . However , Web servers are computers, and like any other computer, things happen for them to fail , or they become old and obsolete and require maintenance and repair . When a host gives you an uptime guarantee of 99%, they say that the web server will be operational for 99 % of the billing period. If they fail to meet this guarantee , most hosts will reimburse some of your money depending on the amount of excess downtime they experienced.

Traffic statistics - statistics programs traffic websites trying to track visitors to your website. They can track the number of times your site is visited , how many visitors were unique and how to return more than once , the pages were the most popular , where visitors came to your site from , what search terms they used in search engines , and many other types of information that may be helpful in marketing your website to a target audience . These statistics can be displayed in tables , charts and tables per hour, day , week, month or year. Some statistics programs are better than others and offer more types of data , better displays, easier navigation and other useful features. Most web hosts now offer some sort of traffic statistics software with hosting packages .

CGI Scripts - Many web hosts offer a variety of free CGI scripts with their packages. These are things like gold hit counters , books, and other programs as messaging , message boards that allow your website to perform functions commonly sought . You can use those to your host offers or you can download and run custom CGI scripts written by yourself or someone else to perform various tasks such as driving a customer information for investigation or processing produce an automatic bid prices . Most CGI scripts are written in common programming languages such as Perl , PHP or ASP .

You could spend a lot of time trying to learn everything there is to know about web hosting, but if you 've read this far , then you should be armed with the basic knowledge you need to understand what different web hosts offer . Your next task is to understand what you need and go out and find a host that wants to give it to you at a great price !

What Web Hosting and How does it work?

noreply@blogger.com (IT Consultant) — Sat, 08 Jun 2013 22:31:00 +0000

Web Hosting

Web hosting is the practice of the business of providing space and bandwidth on a high-powered computer server that is connected to the Internet at high speed. The accommodation maintain large computer networks web servers in a high-power known as a data center physical location companies. These servers are connected to a very fast Internet connection, and generally redundant. Data centers are the primary and backup power, a fast Internet connection, and a staff of security monitoring.

Web hosting companies provide a share of disk space and bandwidth available to a customer for a monthly fee. Once the client is signed, they can upload files to their personal space on the web server and the information is visible to anyone interested on the Internet. The monthly charges for the web hosting company charges is much less than it would cost to run a server on your own home or a data center running. This is why these companies exist. They take care of all the hardware, software and other technical needs for you.

Types of accommodation

There are many different types of accommodation on offer, but the main three are shared, reseller, and dedicated. Each type of accommodation has a different purpose.

Shared Web Hosting

Shared web hosting is the most popular form of accommodation. Shared hosting is a portion of disk space and bandwidth provided to you by the web hosting company on a high-powered server. There are many other hosted on this server websites and the hosting company is likely to have a fairly large number of servers in a data center wide. Server resources are shared by many other sites that are assigned to this computer.

Shared web hosting is the best form of web hosting if you are looking for a great price and do not have more than a few thousands of daily visitors to your site.

Reseller Web Hosting

Reseller web hosting is a popular solution at low cost to start your own web hosting company. There are two types of reseller hosting, private label and reseller services.

The MDD is the best type of reseller plan because it allows you to keep full control over the websites of your customers. Private-label scheme allows the dealer to keep the full monthly payment of web-hosting customer, but the dealer must pay a monthly fee for the largest hosting company for the reseller space. Most accommodation is a private-label reseller can sell, the more profit for them. Private label hosting allows you to host many more sites if you use shared hosting for everyone. This is a great solution for someone who has many sites they need to host a place to save money.

The dealer service plans resell the regular web hosting plans of a large web hosting company, but you get a reduced price to provide customers and earn a monthly fee for as long as they remain a customer. This plan does not allow control over the websites of clients and you do not keep some of the potential monthly income.

Dedicated Web Hosting

Dedicated Web Hosting is the most efficient and economical solution hosting a busy without resorting to buying your own equipment and pay hundreds of dollars per month for a fast connection to the Internet website. The dedicated hosting consists of single server with anyone else hosting on this computer. This allows for more configuration options. Anyone who has a busy find dedicated hosting site is the necessary choice.

Web Hosting Considerations

Wonder about all the other information contained in the web hosting plans? In this section, I will explain the most important considerations in choosing a good web host.

Price

The price of web hosting services is one of the most important. There are many hosting companies out there with cheap hosting packages, but they may be lacking in other areas. Do not let the price of a hosting package fool you. There are some out there hosting companies that have great prices and other characteristics are just as good. The price can be one of the most important features of a web hosting plan decisions, but there is much more to consider in choosing a quality web host.

Disk Space / Storage Space

Disk space is the amount of physical storage space a web host gives you to store your files on the Web. The hosting companies these days have plans with disk space is measured primarily in terms of gigabytes, but some still offer plans in the megabytes of storage space. Depending on your needs storage of files, you may need more or less. In general, the more disk space available, the better.

Bandwidth / Transfer data tape

The amount of available bandwidth can make a big difference in choosing a quality hosting plane. In general, the more bandwidth a hosting company offers the better. This means you can support more traffic to your website as your business grows. Beware of web hosting that offer unlimited bandwidth and unlimited companies. While many of them are legitimate offers, there are some out there who are overselling their bandwidth in the hope that the average user will not use much.

Customer Support

In any business, it is very important to provide exceptional customer service. Web hosting is no exception to this. Many hosting companies are available all day and night if you have a problem with your website, but there are some that are only available specific hours of the day. If your site goes down the middle of the night when they are not available, which means loss of income for a company. You must ensure that the web host you choose is always available for support.

Money back

Most web hosting companies provide a money back guarantee of thirty days. Some even provide a long, but be wary of those who offer no money back guarantee. I would not buy web hosting services from a company that does not offer at least a money back guarantee of 30 days, unless they have been proven to be a leader in the industry and have a excellent reputation.

Operating system

An operating system is software that controls the interaction between the user of the computer and the physical hardware of the machine. A large majority of all websites on the Internet run on the Linux operating system. Linux is generally much more stable than Windows. Stability is essential in the management of a website. For this reason, I prefer to host my web sites on the Linux operating system. Some sites have specific requirements that only the Windows operating system can only meet, but there are always alternatives to these requirements.

Protection

A good web hosting company will have a regular schedule to back up data on all Web servers. In most cases, the data is saved, the better. At the very least, a web hosting company should save the files of the web site every day.

Panel

The control panel is the point of contact the administrator of the website will be between the host server and their own machine connected via the Internet. It is essential to have a control panel interface well organized and easy to use. My favorite control panel is cPanel, which is one of the main panels of web hosting control there today. Plesk is another good, and many companies will create their own control panel that you can use. Most web hosting companies provide a link to a demo of the control panel they use with their hosting plans. The control panel used is a matter of preference, but it should be user friendly.

Email is an essential part of communication on the Internet. Most web hosting companies out there will give you more e-mail addresses and more space to contain e-mail you will ever need. What you need to watch out for is companies that have decided to be a little more strict on their email accounts and only offer a small number or a small amount of space message.

Uptime

Availability is a term used to describe how often the average Web site hosted by a company is available online. Expect any company to provide 100% availability exact. This is possible due to things such as hardware, software, and power outages. A vast majority of companies are very good with availability, and not guaranteed. It is always a good idea to be aware of the uptimes posted by the company. If it is not at least 99.5%, it is probably not worth hosting with this company.

Statistics

As a webmaster, it is good to know how many visitors you had, where they come from, how long they stay on your site, and how much bandwidth they use. This information is collected by the web server and is placed in a log file. A statistical software reads this data and provide useful information to the webmaster. The information gathered from these logs can be very useful in improving service to viewers of the website.

FTP

FTP stands for File Transfer Protocol. This is a way to get online quickly and downloading files to and from a web server. Most web hosting companies will allow their customers to access their web hosting accounts via FTP. FTP is very useful and a great feature to have when you pay for a web hosting account.

Scripting

Since the beginning of the World Wide Web, many scripting languages were created and evolved in dynamic and interactive environment we enjoy today. A scripting language is a way to add functionality to a website, whether it be to calculate numbers or to load information from an external database. Scripting languages have made electronic commerce possible. Some of these languages include PHP, ASP, JSP, ColdFusion, VBScript, JavaScript, and Perl. I will not go into the details of these in this article for reasons of complexity. If you know how to use these languages, you should know what to look for in a web server for them.

Databases

A database is a place to store data that can be used in a variety of ways. The databases are used on the Internet for applications such as shopping carts, message boards and product catalogs. Other databases on the web hosting provider allows you to create, most applications that you can deploy on your web server. The databases are used by the most advanced web master, but the information is available online if you are interested.

Conclusions

Web hosting can be a very difficult decision with thousands of hosting companies out there. It is essential to find a plan that meets your needs and have a good hosting company.

Computer and Keyboard Recycling

noreply@blogger.com (IT Consultant) — Wed, 15 May 2013 19:21:00 +0000

Everyone knows that this is a good thing to do to recycle. If you recycle you keep the earth and reusing materials instead of throwing them in a landfill due to laziness or ignorance. Did you know that there are special companies that are made for the recycling of electronic items in particular?

Electronic items most commonly recycled all the computers and keyboards. Just an article, you can contribute greatly to making the world a better place to live. There are so many different metals and plastics involved in the manufacture of electronic products that are harmful to the environment and taking them out of the picture, we can actually reverse the destruction of the earth rather than help to go forward.

Recycling your keyboard and the computer is easy. All you have to do is call a recycler near you that takes electronics and you just give them a time and place to pick it up. You can also drop if you do not want to come pick it up, but it's just an easy solution for you if you have no obligations.

When they take your items, they will be separated from each other in all different categories depending on the material. Plastics, each type of metal, glass and other information into pieces will be sold separately.

If you insist on an old computer because you're afraid of the information out, you need not worry about that at all. All places of electronics recycling sworn never to touch the hard drives or other equipment that contain confidential information. They will tell you their privacy policies that will allow you to feel relaxed while allowing them to manage your property and exclusive.

They will take your information and have safely appropriately. This means that after they pick you, they will give you a tracking number. You will be able to see where your item is at all times and they will even notify you when it is destroyed. It is guaranteed to be destroyed within 48 hours of collection. This means that all data elements are thrown into a shredder and are sure to be irreparable or even recognizable to this question.

A Beginner's Guide to Avoiding Viruses

noreply@blogger.com (IT Consultant) — Thu, 18 Oct 2012 11:39:00 +0000

I've been invaded by a virus! "Getting means getting sick and no one in their right mind wants to be sick a virus. Well, now that computers have become our close friends, it's a shock to learn that foreign bodies too can invade with malicious intent. No, your computer does not get a runny nose or diarrhea. This is a disease that prevents your friend functioning properly, sick in bed, unable.

Well in nature viruses occur from a power outside of our control. But with computers it's different, humans, mean or ignorant humans are creating these viruses. Why? Usually these are disgruntled people who want to cause havoc on others or companies they believe have hurt for them. In all cases, we must be aware and willing to deal with these debilitating scourges.

There are several approaches to protecting your computer. First, there is the step of awareness. Be aware of how the virus is transmitted. You can catch them from a disk, but in most cases this is because of your messaging system. Check your email address carefully. Be very wary of anything that has an attachment. Make sure it is from and see the title of the e-mail, is this something you expected? Even if it is someone you know, be careful that their computer may be infected and the virus being transmitted without their knowledge.

Then read the cover message, you can not catch the disease without actually opening the message. Look at the name of the attachment, remember viruses are written to entice you. Beware of free and generally all the people you do not know, as well as messages that sound irrelevant usual style of your contact offers. Delete them immediately. Delete, delete, delete. This will ensure a low risk of infection. You can even send the message to the sender without opening it to ensure it is valid.

Now for the heavy protection: Virus scanning and anti-virus software, and spares are readily available and used. Some are free, others are obtained for a very low cost. Most software manufacturers offer subscriptions for updating services, which automatically download protection latest viruses.

There are two main types of virus scanning software: one searches through your entire computer files looking for recognizable viral signatures, the other scans your incoming and outgoing e-mails. Alerts show you when a file should be removed or repaired. If you do get a virus that no software can repair you can send a copy of it to a company like Symantec who will be happy to develop a cure for it.

The main message here is not too worried about your good friend Mrs. PC getting sick or ill. Humans are above the case and they seem much better suited to fixing their technology they are beating the viruses that attack our physical bodies. If only we could beat a human virus and illness as easily as we solve the problem of the computer disease.

10 Secrets To A Healthy Computer And A Happier You

noreply@blogger.com (IT Consultant) — Mon, 15 Oct 2012 21:16:00 +0000

There comes a time in a person's life where no matter how much you fight it time takes its toll and we begin to slow down in how we perform our daily activities. However, in order to extend our youthful glow and energy levels it is important to eat well, exercise, and keep a positive outlook on life.Now you may ask what all this had to do with "Secrets to a healthy computer?"

Well, in a sense, we are all like a computer. If you neglect to take care of yourself you will soon cease to function properly and the many tasks that were once easy to do now take twice as long to accomplish and often require you to rest or "reboot" after a malfunction .I can not tell you what foods to eat or what exercises to do because I am not a nutritionist. Although, with my experiences in the field of personal computing, I can share with you some tips on how to keep that rectangle box of circuitry that is within the operating range of sites at the maximum performance as time permits.

Some important steps to follow are ...

-Make sure your computer is located in a well ventilated area and that all air vents are unobstructed to prevent overheating and premature failure of internal components.

-Clean the dust at least every 6 months from inside the computer case including case vents, power and all visible circuitry with a few cans mouths of compressed air that can be purchased from any major computer store or electronics outlet. This will help reduce the risk of overheating and damage circuits.Before cleaning just be certain to always unplug the computer from the wall outlet and never physically contact the circuitry inside the computer case to prevent damage.

-Be prepared for unexpected always make backups of your important data that you do not have and can not afford to lose failure.I personally keep updated backups of my website and even store the disks in a remote location away from my every day use computers just in case a disaster were to occur and my main computers were destroyed where the need for lost files.

-Purchase and install a well known anti-virus program that can be regularly updated with the latest virus definitions and ran during boot to help protect your computer from being the victim of an unwanted infestation.

-Every two months run "Scandisk" program on your computer follow the "Defragmenter" program to maximize the effectiveness of your hard drive.If you are unsure how to use these utilities and being that the steps to execute these programs varies slightly from one operating system to another, it would be easier to just use the option " Help "which can be found by clicking on the START button button located on the desktop of your computer.The start menu will open a drop-down list box that should display the "Help" option. By going there, you can enter the keywords that deal with the answers to the question you are looking for.

-Start your "Disk Cleanup" utility computers every two weeks or more. If the value of the "Disk Cleanup" utility will automatically empty the recycling bin and recover wasted disk space by deleting temporary Internet files that always seem to accumulate.Again, use the "Help" option if you are unsure of how to perform this task.

-Never smoke near a computer because the fans will pull the smoke in the event that it may cover the internal parts of the computer with a residue which in turn can damage sensitive components.

-Place the computer case in an area where it will not be accidentally kicked or bumped to prevent the loosening of cables and damage to internal components.

-Invest in a high quality surge protector to provide your computer and monitor against voltage spikes or "surges" that can dramatically shorten the life of your system. Like most items in a store, "You get what you pay for." So do not skimp on this important device!Its also not a bad idea to invest in a surge protector that includes what is called a "Protector online data" which allows you to connect your phone lines and plays the same role for the telephone line to your modem as the protector Surge is for lines household electrical current.

-Finally, if you plan to be away from home for more than a few days at a time, or if there is a storm brewing in your area, it's a very wise decision to always unplug all electrical lines and modem telephone lines from your system. Even with a surge protector installed, it is possible that such a large voltage spike such as that caused by a lightning strike could prove fatal to any computer system.

Intel Core 2 Duo Processor

noreply@blogger.com (IT Consultant) — Tue, 28 Jul 2009 18:03:00 +0000

The Intel Core 2 Duo processor was developed to meet the insatiable demand for increased performance from PC users running multiple intense software applications simultaneously.

In the office, PC usage has changed from data entry and word processing to e-Commerce, online collaboration, and an ever-increasing need for continual security and virus protection.

In the home, interests have shifted from low-bandwidth photos and Internet surfing to downloading and viewing high-definition videos, as well as advanced photo and video editing.

Intel’s new 45nm manufacturing technology, with hafniuminfused Hi-k transistors, enables even more processor performance by doubling the transistor density, improving efficiency and speed relative to the previous generation, and increasing cache size by up to 50 percent.

These new Intel Core 2 Duo processors deliver more performance without using more energy.

Built on the innovative Intel® Core™ microarchitecture, the Intel Core 2 Duo desktop processor delivers revolutionary dual-core performance and breakthrough processor energy efficiency.

With Intel® Wide Dynamic Execution, Intel® Smart Memory Access, Intel® Advanced Smart Cache, and Intel® Digital Media Boost, this new processor is designed to do more in less time.

Additional features,which support enhanced security, virtualization, and 64-bit computing, make the Intel Core 2 Duo the most impressive processor developed for an increasingly multimedia-centered, high-definition world.

Energy Efficiency

Design changes in the Intel Core 2 Duo processors that improve performance also increase processor energy efficiency by operating at lower frequencies that require less power to run.

Intel® Intelligent Power Capability, a feature that optimizes energy usage of the processor cores, turns on computing functions only when needed. These more energyefficient processors support smaller, more capable, and quieter desktop PCs to conserve critical power resources.

Better Acoustics

Intel® Core™2 Duo processors are equipped with a Digital Thermal Sensor (DTS) that enables efficient processor and platform thermal control.

Thermal sensors located within the processor measure the maximum temperature on the die at any given time. Intel® Quiet System Technology, included in the Intel® Express Chipset families1, uses the DTS to regulate the system and processor fan speeds.

The acoustic benefit of temperature monitoring is that system fans spin only as fast as needed to cool the system, and slower spinning fans generate less noise.

Core 2 Duo

Core microarchitecture
Desktop CPU
Dual coreUp to 3.33 GHz
Up to 6 MB L2 cache
Up to 1333 MHz FSB
64-bit
Execute Disable bitSSE3, SSSE3, SSE4.1
Virtualization
Trusted Execution
Socket 775

Intel History

noreply@blogger.com (IT Consultant) — Thu, 09 Jul 2009 17:34:00 +0000

Intel is the largest manufacturer of microprocessors in the world, and they got their start by being the brains behind the world's most advanced consumer calculator.In 1972, the Busicom high-powered business calculator was released, and it was powered by an Intel 4004 chip, Intel's first microprocessor.Shortly after, in 1974, Intel broke into the personal computer market when they put their 8080 microprocessor in the Altair 8800, the first successful personal computer ever released.In 1978, Intel struck a deal with IBM to produce the 8088 microprocessor chip to power the brand-new IBM PC for home and small business use. With an ad campaign that featured a re-creation of Charlie Chaplin's "Little Tramp" character, the IBM PC went on to be a huge success and established Intel as a premier microchip manufacturer.

Significance

In 1982, Intel released the 80286 microprocessor, which it eventually shortened to just the 286. This was the first attempt by Intel to create a microchip that could run any of the software written for previous Intel processors. Prior to the release of the 286, none of the Intel processors were backwards compatible--able to run programs written for previous generations of processors. The ability to be backwards compatible with all previous generations is now standard with Intel products. The expanded compatibility of the 286 resulted in the sale of over 15 million personal computers throughout the world.

Time Frame

The 386 generation of microprocessors was released in 1985, and it was the first processor to allow a computer to multi-task, which is the ability to run more than one program simultaneously. The programs were simple, and they were limited to only two or three at one time, but this was a huge jump in technology for home computing.The next generation 486 was released in 1989, and this processor had a built-in math co-processor that allowed it to do complicated computations at a fraction of the time of previous generations. The 486 also allowed for a wider array of colors, and it also allowed for the introduction of true point-and-click technology.Prior to the 486, it was necessary to purchase a math co-processor separately to get the maximum speed out of an Intel microprocessor.

Effects

The Pentium processor was first introduced in 1993 at speeds of 60 Mhz and 66 Mhz. It contained over 3 million transistors that greatly expanded the processor's computing capability and that increased its speed.In 2000, Intel introduced the Pentium 4 family of processors, which featured an initial speed of 1.5 Ghz.Intel continued to make design changes to the Pentium line, which included introducing dual core and quad core processors that were the equivalent of two processors in one and four processors in one.In 2009, Intel finally retired the Pentium name and introduced a new core technology called Merom.

Considerations

The Pentium line of processors was actually going to be called the 586 line, but Intel found it difficult to put patents on a product that was referred to only by a number, so they decided to use the Pentium name instead. The name "Pentium" was created by a marketing firm named Lexicon Branding in 1992 and then used by Intel in its 1993 release. The very first line of Pentium processors was not very successful. A floating point error in the processor caused it to miscalculate on a regular basis, and this prompted one of the largest recalls in the history of the computer industry. It wound up costing Intel over $450 million to recall the defective chips. To avoid the problem ever happening again, Intel created a quality control division that checks each microprocessor before it leaves the factory.

AMD Phenom II Processors

noreply@blogger.com (IT Consultant) — Wed, 08 Jul 2009 17:06:00 +0000

Visual Experience

Live your life in HD. AMD Phenom™ II is for high definition entertainment, gaming, creativity, and beyond. With AMD Phenom™ II processors as the foundation, you'll enjoy a new level of responsiveness and visual intensity. AMD puts high definition computing within everyone’s reach.

Superior technologies for HD video. Enjoy a superior high definition experience for HD videos on you PC. AMD Phenom™ II processor are the powerful engine behind your fidelity, high definition video entertainment experience. Only AMD puts the Ultimate Visual Experience™ for HD video within your reach.

Enjoy entertainment beyond your media library. Get HD content online, offline, wherever you want it, however you want it. Your system can handle whatever you dish out - and serve it up on screen in full, high definition glory.*
Perfect chemistry. Combine AMD Phenom™ II processors and ATI Radeon™ HD graphics to really see the difference. Enjoy smooth video, brilliant videos and immersive games. AMD unleashes visual clarity and responsiveness for what you want to do.

Performance

Do it all. AMD Phenom™ II processors have the power to do it all. Featuring next-generation quad-core design, they crush even the most demanding tasks. So design it, render it, play it, create it, stream it, HD it.* With AMD Phenom™ II processors, if you can imagine it, you can do it.

Energy Efficient

Make a choice you can feel good about. AMD Phenom™ II processors were designed with energy efficiency in mind. Capitalizing on AMD's leadership in energy efficiency, they incorporate all of the latest technology that gives you performance when you need it and save power when you don’t.

AMD Athlon X2

noreply@blogger.com (IT Consultant) — Tue, 07 Jul 2009 16:49:00 +0000

Take multi-tasking to a whole new level with the AMD Athlon™ X2 dual-core processor

AMD Athlon™ X2 dual-core processors put the power of dual-core technology on the desktop. Dual-core processors contain two processing cores, residing on one chip, that perform calculations on two streams of data to increase efficiency and speed while running multiple programs and the new generation of multi-threaded software. For end-users this means a significant increase in response and performance when running multiple applications simultaneously.

Better Multi-Tasking Means Increased Office Productivity

Productivity in today’s workplace requires smooth, efficient and seamless multi-tasking. AMD Athlon™ X2 dual-core processors deliver TRUE multi-tasking, allowing users to switch from one program to another without always pausing for the computer to catch up and reducing annoying processing pauses.

Setting the Pace in Digital Media

Digital media software demands simultaneous processing of data streams, the perfect use for the incredible multi-tasking power of AMD64 dual-core technology. Dual-core technology is like having two processors working together, each one taking care of different applications, so power-users can actually experience greater performance when multiple applications are running. Digital media enthusiasts can usher in the next generation of digital media software for amazing high-definition video and photo editing, content creation, and audio mixing. With an AMD Athlon™ X2 dual-core processor, your PC can perform up to 80% faster than an AMD Athlon™ 4000+ processor on the latest power-hungry digital media software applications.

Get more Power using less Power

Energy-efficient AMD processors with AMD PowerNow!™ Technology (Cool’n’Quiet™ Technology) enable smaller, sleeker, more energy-efficient PC’s. In March 2005, the U.S. Environmental Protection Agency (EPA) awarded AMD PowerNow!™ Technology (Cool’n’Quiet™ Technology) special recognition for the advancement of energy-efficient computer technologies. AMD expects that systems built using energy-efficient AMD desktop processors can meet, and in many instances, exceed the new system requirements from the EPA’s ENERGY STAR Version 4 computer specification, effective July 20, 2007.

All the Proven Benefits of AMD64 Technology

Enhanced Virus Protection with Windows® XP Service Pack 2 and Vista™ Enhanced Virus Protection is a feature enabled by AMD64 technology. Enhanced Virus Protection in conjunction with modern operating systems can help prevent the spread of certain viruses, like MSBlaster and Slammer to significantly reduce the cost and down-time associated with similar viruses and improve the protection of computers and personal information against certain PC viruses.

AMD Athlon Processor Architecture Performance

HyperTransport™ Technology can increase overall system performance by reducing I/O bottlenecks, increasing system bandwidth, and reducing system latency. A fully integrated memory controller helps speed access to memory by giving the processor a direct connection to the main memory. As a result, end users can enjoy quicker application loading and extraordinary application performance.

Ready for the 64-bit future

Like all the processors in the AMD64 family, AMD Athlon™ X2 dual-core processors are designed for people who want to stay at the forefront of technology and for those who depend on their PCs to keep them connected, informed, and entertained. Systems based on AMD64 processors can deliver leading-edge performance for demanding productivity and entertainment software today and in the future.

With AMD64 technology, AMD Athlon™ X2 dual-core processors are fully compatible with existing software, while enabling a seamless transition to 64-bit applications. Both 32- and 64-bit applications can run simultaneously and transparently on the same platform. AMD64 technology enables new, cinematic computing experiences and capabilities, in addition to increased performance. AMD64 technology allows end users to take advantage of new innovations such as real-time encryption, more life-like games, accurate speech interfaces, cinema-quality graphic effects, and easy-to-use video and audio editing.

AMD Turion

noreply@blogger.com (IT Consultant) — Mon, 06 Jul 2009 16:40:00 +0000

Enhanced Memory and Processing

With true multi-core technology, notebook PCs based on AMD Turion™ X2 Ultra Dual-Core Mobile Processors and AMD Turion™ X2 Dual-Core Mobile Processors can deliver significantly greater bandwidth with support for power-optimized HyperTransport™ 3.0 Technology and PCI Express® 2.0, increasing data throughput and improving system performance while helping to extend battery life.

Next-Generation Power Management

Get long battery life with performance on demand. Enhanced AMD PowerNow!™ Technology dynamically switches performance states (processor core voltage and operating frequency) based on processor performance requirements enabling today's more mobile and demanding PC user to extend battery life. With AMD Dynamic Power Management, each processor core, and the integrated memory controller and HyperTransport™ Technology controller are powered by a dedicated voltage plane to give you the performance you need while multitasking on the go. Independent Dynamic Core Technology extends battery life by dynamically optimizing the operating frequency for each core in the processor based on end-user application needs. And AMD CoolCore™ Technology extends notebook usage while on battery by turning off processor features that are not being used.

Range Of Products Provide Smarter Choices For The Money

Choose the right performance for your mobile lifestyle. Mobile solution options include AMD Turion™ X2 Ultra Dual-Core Mobile Processors, which are designed to enable extreme performance and mobility, and AMD Turion™ X2 Dual-Core Mobile Processors, which deliver exceptional performance and long battery life. All to give more choices to today's more mobile PC users.

The Security And Reliability You Want With The Value You Expect For The Long-Term

Run the 32-bit applications of today and the 64-bit applications of tomorrow. Get the advantage of today's powerful applications in a power-efficient notebook PC with the forward-thinking technology to support the advanced applications of the future. Take comfort in security innovations such as Enhanced Virus Protection.

AMD Sempron Processor

noreply@blogger.com (IT Consultant) — Sat, 06 Jun 2009 17:35:00 +0000

AMD Sempron™ Processor Overview

The AMD Sempron™ processor performs at the top of its class when running the home and business applications most. The AMD Sempron™ processor’s full-featured capabilities can include AMD64 Technology, HyperTransport™ technology, up to 256KB total high-performance cache, One 16-bit/16-bit link @ up to 1600MHz full duplex system bus technology, and an integrated DDR2 memory controller.

The AMD Sempron™ processor provides the productivity enhancing performance you need for your everyday applications. It runs over 60,000 of the world’s most popular applications, so you can enjoy solid performance. With 35 years of design and manufacturing experience and shipments of more than 240 million PC processors, you can count on AMD to provide reliable solutions for your home or business.

Affordable - Performance

The AMD Sempron processor performs at the top of its class on the home and business applications that you need and use most.

The AMD Sempron processor is designed for day-to-day computing and beyond.

Full-Featured to Improve your Computing Experience

The AMD Sempron processor lets you enjoy a dynamic Internet experience with smooth streaming video and audio.

The AMD Sempron processor saves you time and effort; enabling your system to boot and load your applications quickly.

Applications that allow you to communicate with family, friends and colleagues will run smoothly with the AMD Sempron processor.

The AMD Sempron™ processor’s advanced architectural features help ensure affordable performance and full-featured capability. These features include:

AMD64 Technology

HyperTransport technology

Up to 256KB total high-performance, full-speed cache

One 16-bit/16-bit link @ up to 1600MHz full duplex system bus technology,

Integrated DDR2 memory controller on certain models

Built-in security with Enhanced Virus Protection* that works with Microsoft® Windows® XP SP2 to help protect against viruses, worms, and other malicious attacks. When combined with protective software, Enhanced Virus Protection is part of an overall security solution that helps keep your information safer.

Enjoy full compatibility with the tools you use daily.
The AMD Sempron processor is designed to run more than 60,000 of the most popular software applications, so you can enjoy reliable performance for a wide variety of computing needs. And since the AMD Sempron processor is compatible with leading PC peripherals, it helps keep everything running smoothly.

Get more value from your PC.
The AMD Sempron processor is ideal for families, students and other budget-conscious or entry-level computer buyers. It includes the right set of features you need for day-to-day computing, and gives you more power for your money than other similar processors. This means you get a PC configured with better components such as CD drives, graphics capabilities, and more.

Reliability from an Industry Leader

AMD is an industry leader that is dedicated to enabling you to get the job done at work or at play.

AMD is constantly striving to find the right solutions for you and your home or business needs.

AMD’s superior quality and track record have long been recognized by a number of the industry’s top publications, organizations and high-tech experts. AMD products, technology, manufacturing, facilities, executives and corporate and community programs have earned a multitude of awards and recognition over the years.

For the latest performance benchmarks and detailed technical documentation of the AMD Sempron processor, please visit Benchmarks and Technical Documentation. For more product comparison information, please visit the AMD Sempron Product Comparison.

AMD Athlon™ 64 Processor

noreply@blogger.com (IT Consultant) — Fri, 05 Jun 2009 17:07:00 +0000

AMD Athlon™ 64 Processor Overview

The AMD Athlon 64 processor is the first Windows®-compatible 64-bit PC processor. The AMD Athlon 64 processor runs on AMD64 technology, a revolutionary technology that allows the processor to run 32-bit applications at full speed while enabling a new generation of powerful 64-bit software applications. Advanced 64-bit operating systems designed for the AMD64 platform from Microsoft, Red Hat, SuSE, and TurboLinux have already been announced.

With the introduction of the AMD Athlon 64 processor, AMD provides customers a solution that can address their current and future computing needs. As the first desktop PC processor to run on the AMD64 platform, the AMD Athlon 64 processor helps ensure superior performance on today’s software with readiness for the coming wave of 64-bit computing. With AMD64 technology, customers can embrace the new capabilities of 64-bit computing on their own terms and achieve compatibility with existing software and operating systems.

Enhanced Virus Protection with Windows® XP Service Pack 2 With a unique combination of hardware and software technologies that offer you an added layer of protection, certain types of viruses don't stand a chance. The AMD Athlon 64 processor features Enhanced Virus Protection, when support by the OS*, and can help protect against viruses, worms, and other malicious attacks. When combined with protective software, Enhanced Virus Protection is part of an overall security solution that helps keep your information safer.

Industry-leading performance for today’s software

It 's not just about email, Web browsing and word processing anymore. The AMD Athlon 64 processor gives you full-throttle performance to go wherever your digital world takes you. Whether you're watching videos, ripping and playing music, or playing games, AMD64 performance helps you to fully enjoy any multimedia experience with a “you are there” reality. The revolutionary architecture of the AMD Athlon 64 processor enables industry-leading performance to help maximize productivity and deliver a true-to-life digital entertainment experience. HyperTransport™ technology can increase overall system performance by removing I/O bottlenecks, increasing system bandwidth, and reducing system latency. A fully integrated DDR memory controller helps speed access to memory by offering the processor a direct connection to the main memory. As a result, end users can enjoy quicker application loading and extraordinary application performance.

With 3DNow!™ Professional technology and support for SSE3, the AMD Athlon 64 processor has more ways to accelerate multimedia applications, enabling stellar performance when working with audio, video, and photography software. For a superior experience with high-speed Internet, the AMD Athlon 64 processor combines high-speed memory access and I/O connectivity to help ensure that end users can fully take advantage of a broadband connection to streaming video and audio, and a riveting online gaming experience.

Ready for the 64-bit future

The AMD Athlon 64 processor is designed for people who want to stay at the forefront of technology and for those who depend on their PCs to keep them connected, informed, and entertained. Systems based on AMD Athlon 64 processors are able to deliver leading-edge performance for demanding productivity and entertainment software today and in the future.

With AMD64 technology, the AMD Athlon 64 processor is fully compatible with existing software, while enabling a seamless transition to 64-bit applications. Both 32- and 64-bit applications can run virtually simultaneously and transparently on the same platform. AMD64 technology enables new, cinematic computing experiences and capabilities, in addition to increased performance. AMD64 technology allows end users to take advantage of new innovations such as real-time encryption, more life-like games, accurate speech interfaces, cinema-quality graphic effects, and easy-to-use video and audio editing.

Protect investments with a technically superior PC processor

The AMD Athlon 64 processor is the world’s most technically advanced PC processor and the first Windows-compatible 64-bit PC processor. Advanced technologies in the AMD Athlon 64 processor include:

-AMD64 technology which doubles the number of processor registers and dramatically increases the system memory addressability

-Enhanced multimedia instructions support including 3DNow! Professional technology and SSE2/3

-With up to a 2000 MHz system bus using HyperTransport technology with up to 14.4 GB/sec total processor-to-system bandwidth

-An integrated memory controller with peak memory bandwidth of up to 6.4 GB/sec, supporting PC3200, PC2700, PC2100, or PC1600 DDR SDRAM

-Native execution of 32-bit software, allowing today’s PC software to provide leading-edge performance while enabling a seamless migration to 64-bit software

The combination of these innovations and features provides customers with performance they need along with tremendous flexibility. Customers can experience outstanding performance running today’s applications and prepare for the next generation of software without having to upgrade or change hardware. For business customers, this extends system life cycles, simplifies technology transition and reduces total cost of ownership.

Purchase with confidence

The AMD Athlon 64 processor is the only industry standard x86 processor with the ability to move beyond the limits of 32-bit computing. The AMD Athlon 64 processor is compatible with Microsoft Windows XP and tens of thousands of PC applications that people around the world use every day. The award-winning AMD Athlon XP processor won over 100 industry accolades and was the first 1GHz PC processor. Now, the AMD Athlon 64 processor reaches a new milestone by building a path to 64-bit computing for millions of PC users.

Founded in 1969, AMD has shipped more than 300 million PC processors worldwide. Customers can depend on the AMD Athlon 64 processor and AMD for compatibility and reliability. AMD processors undergo extensive testing to help ensure compatibility with Microsoft Windows XP, Windows 98, Windows ME, Windows NT®, Windows 2000, as well as Linux and other PC operating systems. AMD works collaboratively with Microsoft and other partners to achieve compatibility of AMD processors and to expand the capability of software and hardware products leveraging AMD64 technology. AMD conducts rigorous research, development, and validation to help ensure the continued integrity and performance of its products.

AMD Processor

noreply@blogger.com (IT Consultant) — Thu, 04 Jun 2009 16:23:00 +0000

Advanced Micro Devices, Inc. (AMD) (NYSE: AMD) is an American multinational semiconductor company based in Sunnyvale, California, that develops computer processors and related technologies for commercial and consumer markets. Its main products include microprocessors, motherboard chipsets, embedded processors and graphics processors for servers, workstations and personal computers, and processor technologies for handheld devices, digital television, automobiles, game consoles, and other embedded systems applications.

AMD is the second-largest global supplier of microprocessors based on the x86 architecture after Intel Corporation, and the third-largest supplier of graphics processing units, behind Intel and Nvidia. It also owns 21 percent of Spansion, a supplier of non-volatile flash memory. In 2007, AMD ranked eleventh among semiconductor manufacturers in terms of revenue.

Advanced Micro Devices was founded on May 1, 1969, by a group of former executives from Fairchild Semiconductor, including Jerry Sanders III, Ed Turney, John Carey, Sven Simonsen, Jack Gifford and three members from Gifford's team, Frank Botte, Jim Giles, and Larry Stenger. The company began as a producer of logic chips, then entered the RAM chip business in 1975. That same year, it introduced a reverse-engineered clone of the Intel 8080 microprocessor. During this period, AMD also designed and produced a series of bit-slice processor elements (Am2900, Am29116, Am293xx) which were used in various minicomputer designs.

During this time, AMD attempted to embrace the perceived shift towards RISC with their own AMD 29K processor, and they attempted to diversify into graphics and audio devices as well as EPROM memory. It had some success in the mid-80s with the AMD7910 and AMD7911 "World Chip" FSK modem, one of the first multistandard devices that covered both Bell and CCITT tones at up to 1200 baud half duplex or 300/300 full duplex. While the AMD 29K survived as an embedded processor and AMD spinoff Spansion continues to make industry leading flash memory, AMD was not as successful with its other endeavors. AMD decided to switch gears and concentrate solely on Intel-compatible microprocessors and flash memory. This put them in direct competition with Intel for x86 compatible processors and their flash memory secondary markets.

AMD announced a merger with ATI Technologies on July 24, 2006. AMD paid $4.3 billion in cash and 58 million shares of its stock for a total of US$5.4 billion. The merger completed on October 25, 2006 and ATI is now part of AMD.

Problem Solving and Programming Logic

noreply@blogger.com (IT Consultant) — Tue, 12 May 2009 07:41:00 +0000

Computer Programs: The Power of Logic

A single program addresses a particular problem. When you write a program, you are solving a problem.

To solve a problem you must use your power of logic and develop an algorithm, or procedure, for solving the problem.

The algorithm is the finite set of step-by-step instructions that convert the input into the desired output, that is, solve the problem.

Structured Program Design: Divide and Conquer

Given a task, programmers were left on their own to create a solution any way they could.

Three major problems arose from this free-form method:
1.Long development time,
2.High maintenance cost, and
3.Low-quality software.

Structured programming stresses the systematic design and management of the program development process.

illustrates a common programming problem:

The printing of weekly payroll checks for hourly and commission employees. In the figure a structure chart is used to break the programming problem into a hierarchy of tasks. The most effective programs are designed to be written in modules, or independent task.

It is much easier to address a complex programming problem in small, more manageable modules than as one big task by using the principles of structured programming.

In structured programming, the logic of the program is addressed hierarchically in logical modules.

BY dividing the program into modules, the structured approach to programming reduces the complexity of the programming task.

Some programs are so complex that if taken as a single task.

Goals of structured programming :

Decrease program development time by increasing programmer productivity and reducing the
time needed to test and debug a program.

Decrease program maintenance costs by reducing errors and making program code easier to understand.

Improve the quality of software by providing programs with fewer errors.

Structured programming accomplishes these goals by incorporating these concepts:

Top-down design and use of modules.
Use of limited control structures (sequence, selection, and repetition).
Management control.

Top-down design starts with the major functions involved in a problem and divides them into subfunctions until the problem has been divided as much as possible.
Each unit is small enough to be programmed by an individual programmer in the required time frame.
This forces an examination of all aspects of a problem on one level before considering the next level.
A programmer is left with small groups, or modules, of processing instructions, which are easy to understand and code.
A program consists of a main logic module that controls the execution of the other modules in the program.
Working from the top down avoids solutions that deal with only part of a problem.
A program that uses a main logic module to control smaller modules is easier to read, test, and maintain.
In structured programming, modules ensure these qualities by:
-having only one entrance and one exit
-performing only one program function
-returning control to the module from which it was received

Programming In Perspective

noreply@blogger.com (IT Consultant) — Mon, 11 May 2009 17:36:00 +0000

What Is Computer Programming ?

Computer programming involves writing instructions and giving them to the computer so it can complete a task.

A computer program, or software, is a set of instructions written in a computer language, intended to be executed by a computer to perform a useful task.

The application packages such as word processors, spreadsheets, and database management systems are computer programs.

A programmer is an individual who translates the tasks that you want a computer to accomplish into a form the computer understands.

What Are The Qualities of a Well-Designed Program?

· Correct and accurate
· Easy to understand
· Easy to maintain and update
· Efficient
· Reliable
· Flexible

Brief of Mac OS

noreply@blogger.com (IT Consultant) — Mon, 20 Apr 2009 21:25:00 +0000

Mac OS is Apple Computer's operating system for Apple Macintosh computers. Mac OS was the first commercially successful operating system which used a graphical user interface. The Macintosh team included Bill Atkinson and Jef Raskin. There are a variety of views on how the Macintosh was developed, and where the underlying ideas originated. While the connection between the Macintosh and the Alto project at Xerox PARC has been established in the historical record, the earlier contributions of Ivan Sutherland's Sketchpad and Doug Engelbart's On-Line System are no less significant. See History of the GUI, and Apple v. Microsoft.

The Mac OS can be divided into two families of operating systems:

An older and now unsupported "classic" Mac OS (the system that shipped with the first Mac in 1984 and its descendants, culminating with Mac OS 9).

The newer Mac OS X (pronunced oh-es-ten). Mac OS X incorporates elements of BSD Unix, OPENSTEP, and Mac OS 9. Its low-level UNIX-based foundation, Darwin, is open source.

Classic Mac OS

The "classic" Mac OS is characterized by its total lack of a command line; it is a 100% graphical operating system. Heralded for its ease of use, it is also criticized for its almost total lack of memory management, cooperative multitasking, and susceptibility to extension conflicts. "Extensions" are program modules that extend the operating system, providing additional functionality (such as a networking) or support for a particular device. Some extensions are prone not to work properly together, or only when loaded in a particular order. Troubleshooting Mac OS extensions can be a time-consuming process. The MacOS also introduced a new type of filesystem, which contained two different "forks" for a file. It was innovative at the time for separating out parameters into the resource fork, and raw data in the "data fork". However, it became quite a challenge to interoperate with other operating systems which did not recognize such a system.

The term "Mac OS" was not officially used until 1996 with the release of Mac OS 7.6 - prior to that the Macintosh operating system software was simply known as "The System", or by its version number, e.g. System 6 or System 7. Another common term was "the Toolbox". Apple deliberately played down the existence of the operating system in the early years of the Mac to help make the machine appear more user-friendly and to distance it from other systems such as MS-DOS, which were portrayed as arcane and technically challenging. With Mac, you turned it on, it just worked.

By the late 1990s, it was clear the useful life of this 1980s-era technology was coming to an end, with other more stable multitasking operating systems being developed.

Mac OS X

Mac OS X remedied this situation, bringing Unix-style memory management and preemptive multitasking. Improved memory management allowed more programs to run at once and virtually eliminated the possibility of one program crashing another. It is also the first Mac OS to include a command line, although it is never seen unless a separate "terminal" program is launched. However, since these new features put higher demands on system resources, Mac OS X is only officially supported on G3 and newer processors. (It runs poorly on many early G3 machines). Mac OS X has a compatibility layer for running older Mac applications, but compatibility is not 100%.

Mac OS Technologies

QuickDraw: the imaging model which first provided mass-market WYSIWYG.

Finder: the interface for browsing the filesystem and launching applications.

MultiFinder: the first version to support simultaneously running multiple apps.

Chooser: tool for accessing network resources (e.g., enabling AppleTalk).

ColorSync: technology for ensuring appropriate color matching.

Mac OS memory management: how the Mac managed RAM and virtual memory before the switch to UNIX.

PowerPC emulation of Motorola 68000: how the Mac handled the architectural transition from

CISC to RISC (see Mac 68K emulator).

Desk Accessories - small "helper" apps that could be run concurrently with any other app, prior to the advent of MultiFinder or System 7.

New Virus in April

noreply@blogger.com (IT Consultant) — Wed, 01 Apr 2009 12:39:00 +0000

An extraordinary behind-the-scenes struggle is taking place between computer security groups around the world and the brazen author of a malicious software program called Conficker.

The program grabbed global attention when it began spreading late last year and quickly infected millions of computers with software code that is intended to lash together the infected machines it controls into a powerful computer known as a botnet.

Since then, the program’s author has repeatedly updated its software in a cat-and-mouse game being fought with an informal international alliance of computer security firms and a network governance group known as the Internet Corporation for Assigned Names and Numbers. Members refer to the alliance as the Conficker Cabal.

The existence of the botnet has brought together some of the world’s best computer security experts to prevent potential damage. The spread of the malicious software is on a scale that matches the worst of past viruses and worms, like the I Love You virus. Last month, Microsoft announced a $250,000 reward for information leading to the capture of the Conficker author.

Botnets are used to send the vast majority of e-mail spam messages. Spam in turn is the basis for shady commercial promotions including schemes that frequently involve directing unwary users to Web sites that can plant malicious software, or malware, on computers.

Botnets can also be used to distribute other kinds of malware and generate attacks that can take commercial or government Web sites off-line.

One of the largest botnets tracked last year consisted of 1.5 million infected computers that were being used to automate the breaking of “captchas,” the squiggly letter tests that are used to force applicants for Web services to prove they are human.

The inability of the world’s best computer security technologists to gain the upper hand against anonymous but determined cybercriminals is viewed by a growing number of those involved in the fight as evidence of a fundamental security weakness in the global network.

“I walked up to a three-star general on Wednesday and asked him if he could help me deal with a million-node botnet,” said Rick Wesson, a computer security researcher involved in combating Conficker. “I didn’t get an answer.”

An examination of the program reveals that the zombie computers are programmed to try to contact a control system for instructions on April 1. There has been a range of speculation about the nature of the threat posed by the botnet, from a wake-up call to a devastating attack.

Researchers who have been painstakingly disassembling the Conficker code have not been able to determine where the author, or authors, is located, or whether the program is being maintained by one person or a group of hackers. The growing suspicion is that Conficker will ultimately be a computing-for-hire scheme. Researchers expect it will imitate the hottest fad in the computer industry, called cloud computing, in which companies like Amazon, Microsoft and Sun Microsystems sell computing as a service over the Internet.

Earlier botnets were devised so they could be split up and rented via black market schemes that are common in the Internet underground, according to security researchers.

The Conficker program is built so that after it takes up residence on infected computers, it can be programmed remotely by software to serve as a vast system for distributing spam or other malware.

Several people who have analyzed various versions of the program said Conficker’s authors were obviously monitoring the efforts to restrict the malicious program and had repeatedly demonstrated that their skills were at the leading edge of computer technology.

For example, the Conficker worm already had been through several versions when the alliance of computer security experts seized control of 250 Internet domain names the system was planning to use to forward instructions to millions of infected computers.

Shortly thereafter, in the first week of March, the fourth known version of the program, Conficker C, expanded the number of the sites it could use to 50,000. That step made it virtually impossible to stop the Conficker authors from communicating with their botnet.

“It’s worth noting that these are folks who are taking this seriously and not making many mistakes,” said Jose Nazario, a member of the international security group and a researcher at Arbor Networks, a company in Lexington, Mass., that provides tools for monitoring the performance of networks. “They’re going for broke.”

Several members of the Conficker Cabal said that law enforcement officials had been slow to respond to the group’s efforts, but that a number of law enforcement agencies were now in “listen” mode.

“We’re aware of it,” said Paul Bresson, an F.B.I. spokesman, “and we’re working with security companies to address the problem.”

A report scheduled to be released Thursday by SRI International, a nonprofit research institute in Menlo Park, Calif., says that Conficker C constitutes a major rewrite of the software. Not only does it make it far more difficult to block communication with the program, but it gives the program added powers to disable many commercial antivirus programs as well as Microsoft’s security update features.

“Perhaps the most obvious frightening aspect of Conficker C is its clear potential to do harm,” said Phillip Porras, a research director at SRI International and one of the authors of the report. “Perhaps in the best case, Conficker may be used as a sustained and profitable platform for massive Internet fraud and theft.”

“In the worst case,” Mr. Porras said, “Conficker could be turned into a powerful offensive weapon for performing concerted information warfare attacks that could disrupt not just countries, but the Internet itself.”

The researchers, noting that the Conficker authors were using the most advanced computer security techniques, said the original version of the program contained a recent security feature developed by an M.I.T. computer scientist, Ron Rivest, that had been made public only weeks before. And when a revision was issued by Dr. Rivest’s group to correct a flaw, the Conficker authors revised their program to add the correction.

Although there have been clues that the Conficker authors may be located in Eastern Europe, evidence has not been conclusive. Security researchers, however, said this week that they were impressed by the authors’ productivity.

Source New York Times

Solaris History

noreply@blogger.com (IT Consultant) — Mon, 30 Mar 2009 02:22:00 +0000

Solaris is the Unix-based operating system developed by Sun Microsystems, displays that company's ability to be innovative and flexible. Solaris, one could argue, is perpetually ahead of the curve in the computer world. Sun continually adapts to the changing computer environment, trying to anticipate where the computer world is going, and what will be needed next, and develops new versions of Solaris to take that into account.

Solaris was born in 1987 out of an alliance between AT&T and Sun Microsystems to combine the leading Unix versions (BSD, XENIX, and System V) into one operating system. Four years later in 1991, Sun replaced it's existing Unix operating system (SunOS 4) with one based on SVR4. This new OS, Solaris 2, contained many new advances, including use of the OpenWindows graphical user interface, NIS+, Open Network Computing (ONC) functionality, and was specially tuned for symmetric multiprocessing.

This kicked off Solaris' history of constant innovation, with new versions of Solaris being released almost annually over the next fifteen years. Sun was constantly striving to stay ahead of the curve, while at the same time adapting Solaris to the existing, constantly evolving wider computing world. The catalogue of innovations in the Solaris OS are too numerous to list here, but a few milestones are worth mentioning. Solar 2.5.1 in 1996 added CDE, the NFSv3 file system and NFS/TCP, expanded user and group IDs to 32 bits, and included support for the Macintosh PowerPC platform. Solaris 2.6 in 1997 introduced WebNFS file system, Kerberos 5 security encryption, and large file support to increase Solaris' internet performance.

Solaris 2.7 in 1998 (renamed just Solaris 7) included many new advances, such as native support for file system meta-data logging (UFS logging). It was also the first 64-bit release, which dramatically increased its performance, capacity, and scalability. Solaris 8 in 2000 took it a step further was the first OS to combine datecentre and dot-com requirements, offering support for IPv6 and IPSEC, Multipath I/O, and IPMP. Solaris 9 in 2002 saw the writing on the wall of the server market, dropped OpenWindows in favour of Linux compatibility, and added a Resource Manager, the Solaris Volume Manager, extended file attributes, and the iPlanet Directory Server.

Solaris 10, the current version, was released to the public in 2005 free of charge and with a host of new developments. The latest advances in the computing world are constantly being incorporated in new versions of Solaris 10 released every few months. To mention just a few, Solaris features more and more compatibility with Linux and IBM systems, has introduced the Java Desktop System based on GNOME, added Dynamic Tracing (Dtrace), NFSv4, and later the ZFS file system in 2006.

Also in 2006, Sun set up the OpenSolaris Project. Within the first year, the OpenSolaris community had grown to 14,000 members with 29 user groups globally, working on 31 active projects. Although displaying a deep commitment to open-source ideals, it also provides Sun with thousands of developers essentially working for free.

The development of the Solaris OS demonstrates Sun Microsystems' ability to be on the cutting edge of the computing world without losing touch with the current computing environment. Sun regularly releases new versions of Solaris incorporating the latest development in computer technology, yet also included more cross-platform compatibility and incorporating the advances of other systems. The OpenSolaris project is the ultimate display of these twin strengths-Sun has tapped into the creative energy of developers across the world and receives instant feedback about what their audience wants and needs. If all software companies took a lesson from Sun, imagine how exciting and responsive the industry could be.

Linux History

noreply@blogger.com (IT Consultant) — Mon, 23 Mar 2009 17:26:00 +0000

In order to know the popularity of linux, we need to travel back in time. In earlier days, computers were like a big house, even like the stadiums. So there was a big problem of size and portability. Not enough, the worst thing about computers is every computer had a different operating system. Software was always customized to serve a specific purpose, and software for one given system didn't run on another system. Being able to work with one system didn't automatically mean that you could work with another. It was difficult, both for the users and the system administrators. Also those computers were quiet expensive. Technologically the world was not quite that advanced, so they had to live with the size for another decade. In 1960, a team of developers in the Bell Labs laboratories started working on a solution or the software problem, to address these compatibility issues. They developed a new operating system, which was simple, elegant , written in C Programming language instead of Assebly language and most important is it can be able to recycle the code. The Bell Labs developers named their this project as " UNIX ".

Unix was developed with small piece of code which is named as kernel. This kernel is the only piece of code that needs to be adapted for every specific system and forms the base of the UNIX system. The operating system and all other functions were built around this kernel and written in a higher programming language, C. This language was especially developed for creating the UNIX system. Using this new technique, it was much easier to develop an operating system that could run on many different types of hardware. So this naturally affected the cost of Unix operating system, the vendors used to sell the software ten times than the original cost. The source code of Unix, once taught in universities courtesy of Bell Labs, was not published publicly. So developers tried to find out some solution to to provide an efficient solution to this problem.

A solution seemed to appear in form of MINIX. It was written from scratch by Andrew S. Tanenbaum, a US-born Dutch professor who wanted to each his students the inner workings of a real operating system. It was designed to run on the Intel 8086 microprocessors that had flooded the world market.

As an operating system, MINIX was not a superb one. But it had the advantage that the source code was available. Anyone who happened to get the book 'Operating Systems: Design and Implementation' by Tanenbaum could get hold of the 12,000 lines of code, written in C and assembly language. For the first time, an aspiring programmer or hacker could read the source codes of the operating system, which to that time the software vendors had guarded vigorously. A superb author, Tanenbaum captivated the brightest minds of computer science with the elaborate lively discussion of the art of creating a working operating system. Students of Computer Science all over the world worked hard over the book, reading through the codes to understand the very system that runs their computer.

And one of them was Linus Torvalds. Linus Torvalds was the second year student of Computer Science at the University of Helsinki and a self- taught hacker. MINIX was good, but still it was simply an operating system for the students, designed as a teaching tool rather than an industry strength one. At that time, programmers worldwide were greatly inspired by the GNU project by Richard Stallman, a software movement to provide free and quality software. In the world of Computers, Stallman started his awesome career in the famous Artificial Intelligence Laboratory at MIT, and during the mid and late seventies, created the Emacs editor.

In the early eighties, commercial software companies lured away much of the brilliant programmers of the AI lab, and negotiated stringent nondisclosure agreements to protect their secrets. But Stallman had a different vision. His idea was that unlike other products, software should be free from restrictions against copying or modification in order to make better and efficient computer programs. With his famous 1983 manifesto that declared the beginnings of the GNU project, he started a movement to create and distribute softwares that conveyed his philosophy (Incidentally, the name GNU is a recursive acronym which actually stands for 'GNU is Not Unix'). But to achieve this dream of ultimately creating a free operating system, he needed to create the tools first. So, beginning in 1984, Stallman started writing the GNU C Compiler (GCC), an amazing feat for an individual programmer. With his smart technical skills, he alone outclassed entire groups of programmers from commercial software vendors in creating GCC, considered as one of the most efficient and robust compilers ever created.

Linus himself didn't believe that his creation was going to be big enough to change computing forever. Linux version 0.01 was released by mid September 1991, and was put on the net. Enthusiasm gathered around this new kid on the block, and codes were downloaded, tested, tweaked, and returned to Linus. 0.02 came on October 5th.

Further Development

While Linux development, Linus faced some of the difficulties such as cross opinions with some people. E.g. Tanenbaum the great teacher who wrote the MINIX. He sent the letter to Linus as :-

“I still maintain the point that designing a monolithic kernel in 1991 is a fundamental error. Be thankful you are not my student. You would not get a high grade for such a design " Linus later admitted that it was the worst point of his development of Linux. Tanenbaum was certainly the famous professor, and anything he said certainly mattered. But he was wrong with Linux, for Linus was one stubborn guy who never like defeats. Although, Tanenbaum also remarked that “Linux is obsolete.” So very soon thousands of people form a community and all joined the camp. Powered by programs from the GNU project, Linux was ready for the actual showdown. It was licensed under GNU General Public License, thus ensuring that the source codes will be free for all to copy, study and to change. Students and computer programmers grabbed it.

Everyone tried and edited the source code and then it gives the start for commercial vendors to start their market. They compiled various software and distributed them with that operating system which people are familiar with. Red Hat, Debian gained more response from outside world. With the new graphical interface system like KDE, GNONE the linux becomes popular. The best thing today about Linux is it's powerful commands.

Rise of the Desktop Linux

What is the biggest complaint about Linux ??? That is it's Text mode. Many people get scared of seeing the command base interface which is not understandable. But if anyone starts learning the commands, it goes on interesting topics to learn new about the Operating System. Still now, very friendly GUI's are available for it's flexibility. Anyone can install the Linux without having the prior experience. Everything is well explanatory at the time of installation. Most distributions are also available in Live CD format, which the users can just put in their CD drives and boot without installing it to the hard drive, making Linux available to the newbies. The most important point about Linux is it's open source. So Computer users having low budget can have Linux and learn linux as it is free.

Linux's Logo - Penguin

The logo of Linux is Penguin. It's called as Tux in technological world. Rather Tux, as the penguin is lovingly called, symbolizes the carefree attitude of the total movement. This cute logo has a very interesting history. As put forward by Linus, initially no logo was selected for Linux. Once Linus went to the southern hemisphere on a vacation. There he encountered a penguin,not unlike the current logo of Linux. As he tried to pat it, the penguin bit his hand. This amusing incident led to the selection of a penguin as the logo of Linux sometime later.

Unix History

noreply@blogger.com (IT Consultant) — Tue, 17 Mar 2009 19:41:00 +0000

Since it began to escape from AT&T's Bell Laboratories in the early 1970's, the success of the UNIX operating system has led to many different versions: recipients of the (at that time free) UNIX system code all began developing their own different versions in their own, different, ways for use and sale. Universities, research institutes, government bodies and computer companies all began using the powerful UNIX system to develop many of the technologies which today are part of a UNIX system.

Computer aided design, manufacturing control systems, laboratory simulations, even the Internet itself, all began life with and because of UNIX systems. Today, without UNIX systems, the Internet would come to a screeching halt. Most telephone calls could not be made, electronic commerce would grind to a halt and there would have never been "Jurassic Park"!

By the late 1970's, a ripple effect had come into play. By now the under- and post-graduate students whose lab work had pioneered these new applications of technology were attaining management and decision-making positions inside the computer system suppliers and among its customers. And they wanted to continue using UNIX systems.

Soon all the large vendors, and many smaller ones, were marketing their own, diverging, versions of the UNIX system optimized for their own computer architectures and boasting many different strengths and features. Customers found that, although UNIX systems were available everywhere, they seldom were able to interwork or co-exist without significant investment of time and effort to make them work effectively. The trade mark UNIX was ubiquitous, but it was applied to a multitude of different, incompatible products.

In the early 1980's, the market for UNIX systems had grown enough to be noticed by industry analysts and researchers. Now the question was no longer "What is a UNIX system?" but "Is a UNIX system suitable for business and commerce?"

Throughout the early and mid-1980's, the debate about the strengths and weaknesses of UNIX systems raged, often fuelled by the utterances of the vendors themselves who sought to protect their profitable proprietary system sales by talking UNIX systems down. And, in an effort to further differentiate their competing UNIX system products, they kept developing and adding features of their own.

In 1984, another factor brought added attention to UNIX systems. A group of vendors concerned about the continuing encroachment into their markets and control of system interfaces by the larger companies, developed the concept of "open systems."

Open systems were those that would meet agreed specifications or standards. This resulted in the formation of X/Open Company Ltd whose remit was, and today in the guise of The Open Group remains, to define a comprehensive open systems environment. Open systems, they declared, would save on costs, attract a wider portfolio of applications and competition on equal terms. X/Open chose the UNIX system as the platform for the basis of open systems.

Although UNIX was still owned by AT&T, the company did little commercially with it until the mid-1980's. Then the spotlight of X/Open showed clearly that a single, standard version of the UNIX system would be in the wider interests of the industry and its customers. The question now was, "which version?".

In a move intended to unify the market in 1987, AT&T announced a pact with Sun Microsystems, the leading proponent of the Berkeley derived strain of UNIX. However, the rest of the industry viewed the development with considerable concern. Believing that their own markets were under threat they clubbed together to develop their own "new" open systems operating system. Their new organization was called the Open Software Foundation (OSF). In response to this, the AT&T/Sun faction formed UNIX International.

The ensuing "UNIX wars" divided the system vendors between these two camps clustered around the two dominant UNIX system technologies: AT&T's System V and the OSF system called OSF/1. In the meantime, X/Open Company held the center ground. It continued the process of standardizing the APIs necessary for an open operating system specification.

In addition, it looked at areas of the system beyond the operating system level where a standard approach would add value for supplier and customer alike, developing or adopting specifications for languages, database connectivity, networking and mainframe interworking. The results of this work were published in successive X/Open Portability Guides.

XPG 4 was released in October 1992. During this time, X/Open had put in place a brand program based on vendor guarantees and supported by testing. Since the publication of XPG4, X/Open has continued to broaden the scope of open systems specifications in line with market requirements. As the benefits of the X/Open brand became known and understood, many large organizations began using X/Open as the basis for system design and procurement. By 1993, over $7 billion had been spent on X/Open branded systems. By the start of 1997 that figure has risen to over $23 billion. To date, procurements referencing the Single UNIX Specification amount to over $5.2 billion.

In early 1993, AT&T sold it UNIX System Laboratories to Novell which was looking for a heavyweight operating system to link to its NetWare product range. At the same time, the company recognized that vesting control of the definition (specification) and trademark with a vendor-neutral organization would further facilitate the value of UNIX as a foundation of open systems. So the constituent parts of the UNIX System, previously owned by a single entity are now quite separate

In 1995 SCO bought the UNIX Systems business from Novell, and UNIX system source code and technology continues to be developed by SCO.

In 1995 X/Open introduced the UNIX 95 brand for computer systems guaranteed to meet the Single UNIX Specification. The Single UNIX Specification brand program has now achieved critical mass: vendors whose products have met the demanding criteria now account for the majority of UNIX systems by value.

For over ten years, since the inception of X/Open, UNIX had been closely linked with open systems. X/Open, now part of The Open Group, continues to develop and evolve the Single UNIX Specification and associated brand program on behalf of the IT community. The freeing of the specification of the interfaces from the technology is allowing many systems to support the UNIX philosophy of small, often simple tools , that can be combined in many ways to perform often complex tasks. The stability of the core interfaces preserves existing investment, and is allowing development of a rich set of software tools. The Open Source movement is building on this stable foundation and is creating a resurgence of enthusiasm for the UNIX philosophy. In many ways Open Source can be seen as the true delivery of Open Systems that will ensure it continues to go from strength to strength.

OS/2

noreply@blogger.com (IT Consultant) — Mon, 09 Mar 2009 17:55:00 +0000

A family of multitasking operating systems for x86 machines from IBM. OS/2 Warp is the client version, and Warp Server is the server version. With add-ons, DOS and Windows applications can also be run under OS/2 (see Odin). The server version includes advanced features such as the journaling file system (JFS) used in IBM's AIX operating system. Like Windows, OS/2 provides a graphical user interface and a command line interface. See OS/2 Warp, Warp Server and eComStation.

Although highly regarded as a robust operating system, OS/2 never became widely used. However, it has survived in the banking industry, especially in Europe, and many ATM machines in the U.S. have continued to run OS/2 due to its stability.

Features

OS/2 includes Adobe Type Manager for rendering Type 1 fonts on screen and providing PostScript output on non-PostScript printers. OS/2's dual boot feature allows booting up into OS/2 or DOS.

The OS/2 Workplace Shell graphical user interface is similar to Windows and the Macintosh. Originally known as Presentation Manager (PM), after Version 2.0, PM referred to the programming interface (API), not the GUI interface itself.

Evolution

The first versions of OS/2 were single-user operating systems written for 286s and jointly developed by IBM and Microsoft. Starting with Version 2.0, versions were written for 32-bit 386s and up and were solely the product of IBM. Following is some of the evolution:

OS/2 16-bit Version 1.x

The first versions (1.0, 1.1, etc.) were written for the 16-bit 286. DOS compatibility was limited to about 500K. Version 1.3 (OS/2 Lite) required 2MB RAM instead of 4MB and included Adobe Type Manager. IBM's Extended Edition version included Communications Manager and Database Manager.

OS/2 32-bit Version 2.x - IBM

Introduced in April 1992, this 32-bit version for 386s from IBM multitasked DOS, Windows and OS/2 applications. Data could be shared between applications using the clipboard and between Windows and PM apps using the DDE protocol. Version 2.x provided each application with a 512MB virtual address space that allowed large tasks to be easily managed.

Version 2.1 supported Windows' Enhanced Mode and applications could take full advantage of Windows 3.1. It also provided support for more video standards and CD-ROM drives.

Communications and database management for OS/2 were provided by Communications Manager/2 (CM/2) and Database Manager/2 (DB2/2). CM/2 replaced Communications Manager, which was part of OS/2 2.0's Extended Services option.

OS/2 32-bit Version 3 - IBM

In late 1994, IBM introduced Version 3 of OS/2, renaming it OS/2 Warp. The first version ran in only 4MB of memory and included a variety of applications, including Internet access.

Windows NT - Microsoft

Originally to be named OS/2 Version 3.0, this 32-bit version from Microsoft was renamed "Windows NT" and introduced in 1993. See Windows NT.

How Will I Use an Operating System?

noreply@blogger.com (IT Consultant) — Thu, 26 Feb 2009 22:53:00 +0000

The user interface of an operating system is the portion of the program with which users interact.
The user interface can be

1. Command-line,
2.Menu-driven, and
3.Graphics-based.

A command-line interface requires a user to type the desired response at a prompt using a special command language.

To be an effective user of any command-line software, you must memorize its commands and their exact syntax-no easy task.

A menu-driven interface allows the user to select commands from a list (menu) using the keyboard or a pointing device such as a mouse.

A graphical user interface (GUI):

The trend is away from text-based, command-line interfaces to user-friendly, graphics-oriented environment called a graphical user interface (GUI).

Graphical user interfaces rely on graphics-based software.

Graphic-based software permits the integration of text with high-resolution graphic
image, called icons.

GUI users interact with the operating system and other software packages by using a pointing device and a keyboard to issue commands.

Rather than enter a command directly, the user chooses from options displayed on the screen.

The equivalent of a syntax-sensitive operating system command is entered by pointing to and choosing one or more options from menu or by pointing to and choosing a graphics image, called an icon.

Typically GUI includes some or all of the following parts:

-Icons, which are graphical images that represent items, such as files and directories.
-Agraphical pointer, which is controlled by a pointing device (mouse), to select icons and
commands and move on-screen items.
-On-screen pull-down menus that appear or disappear, controlled by the pointing device.
-Windows that enclose applications or objects on the screen.

GUIs have effectively eliminated the need for users to memorize and enter cumbersome commands.

Type of Processing

noreply@blogger.com (IT Consultant) — Thu, 26 Feb 2009 22:43:00 +0000

A multiprocessing operating system allows the simultaneous execution of programs by a computer that has two or more CPUs. Each CPU can be either dedicated to one program, or dedicated to specific functions and then used by all programs.

Interprocessing, also called dynamic linking, is a type of processing that allows any change made in one application to be automatically reflected in any related, linked application.

Real-time processing allows a computer to control or monitor the performance of other machines and people by responding to input data in a specified amount of time.

Virtual-machine (VM) processing creates the illusion that there is more than one physical machine. VM capabilities permit a computer to run numerous operating systems at one time. VM capabilities are typically used on supercomputers and mainframes.

Virtual memory, also called virtual storage, allows you to use a secondary-storage device as an extension of main memory. Virtual memory resolves the problem of insufficient main memory to contain an entire program and its data.

Major Functions of Operating Systems

noreply@blogger.com (IT Consultant) — Thu, 26 Feb 2009 20:19:00 +0000

The major functions of an OS are:

-resource management,
-data management,
-job (task) management, and
-standard means of communication between user and computer.

The resource management function of an OS allocates computer resources such as CPU time, main memory, secondary storage, and input and output devices for use.

The data management functions of an OS govern the input and output of the data and their location, storage, and retrieval.

The job management function of an OS prepares, schedules, controls, and monitors jobs submitted for execution to ensure the most efficient processing. A job is a collection of one or more related programs and their data.

A job is a collection of one or more related programs and their data.

The OS establishes a standard means of communication between users and their computer systems. It does this by providing a user interface and a standard set of commands that control the hardware.

Typical Day-to-Day Uses of an Operating System

-Executing application programs.
-Formatting floppy diskettes.
-Setting up directories to organize your files.
-Displaying a list of files stored on a particular disk.
-Verifying that there is enough room on a disk to save a file.
-Protecting and backing up your files by copying them to other disks for safekeeping.

How Do Operating Systems Differ?

Operating systems for large computers are more complex and sophisticated than those for microcomputers because the operating systems for large computers must address the needs of a very large number of users, application programs, and hardware devices, as well as supply a host of administrative and security features.

Operating system capabilities can be described in terms of

-the number of users they can accommodate at one time,
-how many tasks can be run at one time, and
-how they process those tasks.

Number of Users:

A single-user operating system allows only one user at a time to access a computer.

Most operating systems on microcomputers, such as DOS and Window 95, are single-user access systems.

A multiuser operating system allows two or more users to access a computer at the same time (UNIX).

The actual number of users depends on the hardware and the OS design.
Time sharing allows many users to access a single computer.
This capability is typically found on large computer operating systems where many users need access at the same time.

Number of Tasks

An operating system can be designed for single tasking or multitasking.

A single tasking operating system allows only one program to execute at a time, and the program must finish executing completely before the next program can begin.

A multitasking operating system allows a single CPU to execute what appears to be more than one program at a time.

Context switching allows several programs to reside in memory but only one to be active at a time. The active program is said to be in the foreground. The other programs in memory are not active and are said to be in the background. Instead of having to quit a program and load another, you can simply switch the active program in the foreground to the background and bring a program from the background into the foreground with a few keystrokes.

Cooperative multitasking in which a background program uses the CPU during idle time of the foreground program. For example, the background program might sort data while the foreground program waits for a keystroke.

Time-slice multitasking enables a CPU to switch its attention between the requested tasks of two or more programs. Each task receives the attention of the CPU for a fraction of a second before the CPU moves on to the next. Depending on the application, the order in which tasks receive CPU attention may be determined sequentially (first come first served) or by previously defined priority levels.

Multithreading supports several simultaneous tasks within the same application. For example, with only one copy of a database management system in memory, one database file can be sorted while data is simultaneously entered into another database file.

Operating System

noreply@blogger.com (IT Consultant) — Fri, 20 Feb 2009 21:02:00 +0000

What Is an Operating System?

An operating system (OS) is a core set of programs that control and supervise the hardware resources of a computer and provide services to other system software, application software, programmers, and users of a computer.

The OS gives the computer the instructions it needs to operate, telling it how to interact with hardware, other software, and the user.

The OS establishes a standard interface, or means of communication, between users and their computer systems.
When you power up a computer, you boot the system.
The booting procedure is so named because the computer "pulls itself up by its own bootstraps" (without the assistance of humans).
When booting the system,

First, a program in read-only memory (ROM) initializes the system and runs a system check to verify that the electronic components are operational and readies the computer for processing.
Next, the operating system is loaded to RAM, takes control of the system, and presents the user with a system prompt or a GUI screen full of options.

Operating System Parts

Operating systems are composed of two major parts:

control programs, and
service program.

Control programs manage computer hardware and resources.
The main program in most operating systems is the supervisor program.

A supervisor program is a control program that is known in some operating systems as the monitor, executive, or kernel.
The supervisor program is responsible for controlling all other OS programs as well as other system and application programs.
The supervisor program controls the activities of all of the hardware components of a computer.

Service programs are external OS programs that provides a service to the user or programmer of a computer.
They must be loaded separately because they are not automatically loaded when the operating system is loaded.
They perform routine but essential functions, such as formatting a disk for use and copying files from one location to another.