An operating system (OS) is a collection of software that manages computer hardware resources and provides common services for computer programs. The operating system is a vital component of the system software in a computer system. Application programs usually require an operating system to function.
Time-sharing operating systems schedule tasks for efficient use of the system and may also include accounting for cost allocation of processor time, mass storage, printing, and other resources.
For hardware functions such as input and output and memory allocation, the operating system acts as an intermediary between programs and the computer hardware, although the application code is usually executed directly by the hardware and will frequently make a system call to an OS function or be interrupted by it. Operating systems can be found on almost any device that contains a computer—from cellular phones and video game consoles to supercomputers and web servers.
Examples of popular modern operating systems include Android, BSD, iOS, Linux, Mac OS X, Microsoft Windows, Windows Phone, and IBM z/OS. All these, except Windows and z/OS, share roots in UNIX.
Famous quotes containing the words operating and/or system:
“Many people operate under the assumption that since parenting is a natural adult function, we should instinctively know how to do itand do it well. The truth is, effective parenting requires study and practice like any other skilled profession. Who would even consider turning an untrained surgeon loose in an operating room? Yet we operate on our children every day.”
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“Human beings are compelled to live within a lie, but they can be compelled to do so only because they are in fact capable of living in this way. Therefore not only does the system alienate humanity, but at the same time alienated humanity supports this system as its own involuntary masterplan, as a degenerate image of its own degeneration, as a record of peoples own failure as individuals.”
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