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operating system - Student Encyclopedia (Ages 11 and up)

The operation of a computer is controlled by software known as the operating system (OS). This software is as important to the running of a computer as its hardware. The operating system directs the input and output of data, keeps track of files, and controls the processing of computer programs, allocating computer resources to various functions. The operating system also serves as an interface between the computer and the user. Most computer programs complete a task and then end. An operating system, on the other hand, runs indefinitely and terminates only when the computer is turned off. Microsoft’s Windows OS and Apple Inc.’s Mac OS are examples of operating systems for personal computers.

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