Operating System

The old definition of an operating system in early 60's was that it is “the software that controls the hardware". It is set of Programs that make hardware useable or an operating system is the set of programs that controls a computer. Some examples of operating systems are UNIX, Windows Vista, Mach, MS-DOS, MS-Windows, Windows/NT, Chicago, OS/2, MacOS, VMS, MVS, and VM.O/s is about system control.
System Control includes software at several levels. It includes kernel services, library services, and  services at application level. Processes run functions, which are linked together with libraries that perform various standard services. The kernel supports the processes by providing a path to the Secondary devices.

Operating system definition
An Operating System, or OS, is a software program that enables the computer hardware to communicate and operate with the computer software.

The operating system controls your computer's tasks and manages system resources to optimize performance. Learn how your operating system works.

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