1. INTRODUCTION TO OPERATING SYSTEM

Introduction to Operating system
An operating system (OS) is system software that manages computer hardware and software resources and provides common services for computer programs. All computer programs, excluding firmware, require an operating system to function.


An operating system is a program that acts as an interface between the user and the computer hardware and controls the execution of all kinds of application programs and assistant system software programs (i.e. Utilities).


Basic importance of the operating system
1) Operating system behaves as a resource manager. It utilizes the computer in a cost effective manner. It keeps account of different jobs and the where about of their results and locations in the memory.
2) Operating system schedules jobs according to their priority passing control from one program to the next. The overall function of job control is especially important when there are several uses (a multi user environment)
3) Operating system makes a communication link user and the system and helps the user to run application programs properly and get the required output
4) Operating system has the ability to fetch the programs in the memory when required and not all the Operating system to be loaded in the memory at the same time, thus giving the user the space to work in the required package more conveniently and easily.
5) Operating system helps the user in file management. Making directories and saving files in them is a very important feature of operating system to organize data according to the needs of the user
6) Multiprogramming is a very important feature of operating system. It schedules and controls the running of several programs at ones
7) It provides program editors that help the user to modify and update the program lines
8) Debugging aids provided by the operating system helps the user to detect and rename errors in programs
9) Disk maintenance ability of operating system checks the validity of data stored on diskettes and other storage to make corrections to erroneous data Operating