An operating system is the most important software that runs on a computer. It manages the computer's memory, processes, and all of its software and hardware. It also allows you to communicate with the computer without knowing how to speak the computer's "language." Without an operating system, a computer is useless.

The Operating System's Job
You've probably heard the phrase boot your computer, but do you know what that means? Booting is the process that occurs when you press the power button to turn your computer on. During this process (which may take a minute or two), the computer does several things:
- It runs tests to make sure everything is working correctly.
- It checks for new hardware.
- It then starts up the operating system.
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PC Windows 7

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Mac OS X



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iPad Apple IOS