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What is the operating system? Why do you need one? Can you save some money by not getting an OS? These and other topics will be discussed in this article.

Some computer products do not have an OS; they are hard wired with a single program and perform one function. An example is a wrist watch, which does not have to control peripheral devices. Another example is a microwave oven, where you just key in the time and other functions, and it cooks.

The desk top computer on the other hand communicates with many peripheral devices and many programs, each in a different way. Because of the variety of things the computer can do, it requires an interfacing piece of software, between the hardware and the commercial programs. This interface is the operating system.

When you type the letter "A" on the keyboard and the letter "A" appears on the monitor; think of everything going on in the background. The digitized information is going from the keyboard to the CPU, and then it is sent to the monitor. In between there are separate pieces of software controlling each device, these are drivers. The drivers are provided by the manufacturer of each peripheral, and then added to the OS. This of course, is over simplified.

When you first install the operating system, there are hundreds of drivers present and not activated. When the computer is powered up the OS searches for the plug and play peripherals attached; if they are present, the drivers are activated. If not, you are given the option of installing the drivers from disk, or downloading them over the Internet. They become an integral part of the OS

The memory manager is another part of the OS; its job is to allocate memory to each program. The memory manager makes sure none of the processes overlap and run into each other in the same memory space. It also makes sure data is kept separate, and each page of data does not run into one another. Additionally it tracks everything so when needed it can be located fast.

The file system tracks how the data is read and written to the hard drive, DVD, and the CD. Using administrative features it allows different people access or no access to files. Some people can read and not modify files; others have the ability to modify files. These are powerful security features of the operating system.

The interrupt system allows programs to be running, and when you press the "A" key, an interrupt signal is sent to the processor, causing a different program to handle the typed character. This allows for not having to create software to anticipate the typing of a key. Additionally this holds true when a message comes over the Internet, it is handled the same way.

The OS is a dynamic growing entity, as new features are requested by end-users, they are added. When service packs are provided they contain improvements to these features. As newer versions of the OS are released these features are improved and enhanced. Features that are no longer of interest to the public are phased out.

This is a sample of the processes that the OS provides, so you can begin to see its robustness, also, how important it is to good computer management. For desk top computers the major operating systems are Windows by Microsoft, Mac OS X by Apple, and Unix/Linux.

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For additional information about the Operating System.

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