Operating system (OS) is a program that primarily manages all other programs on a computer after a boot program is loaded on the computer. Other programs are called applications or application programs. The application program uses the operating system by requesting services through a specific application program interface (API).

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A multitasking operating system where multiple programs can run simultaneously, the operating system determines how an application should run and how much time each app should offer before making another change for another application. It's internal memory in multiple applications. It handles inputs and outputs from connected hardware devices like hard disks, printers and dial-up ports.

Kinds of Operating System:

The world's most popular and easy-to-use operating system (OS) is the Windows operating system (OS), then the Linux operating system (OS).

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Mobile Operating System

Mobile phone popular operating system is Android OS, iOS , Firefox OS, Windows OS.

Others OS or Operating System

1. Haiku, 2. React OS, 3. Aros, 4. Inferno, 5. Kolibri OS, 6. Dex OS, 7. Free VMS, 8. JNODE, 9. Syllable

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Without the operating system, your computer will only be able to do one thing at a time. At present, the computer completes one process at a time, but the OS completes this process so that you can not understand when multitational tasking is done, the computer is working on one. So I have clearly understood now how a computer can be operated without the operating system.