OPERATION SYSTEM
The operating system (OS) is the most primary program that runs on a computer. The OS allows
computers to run all programs on it. Computer operating systems perform fundamental tasks,
such as recognizing input from the keyboard and send output to the screen, deal with files on
storage sites controlling peripheral devices.
Multi-user
it allows two or more users to work on a program at the same time. Some
operating systems permit hundreds or even thousands users.
Multiprocessing
it supports running a program on more than one desktop.
Multitasking
it allows more than one program to run simultaneously.
Multithreading
it allows different parts of a single program to run synchronously.
Real time
it responds to input instantly.