What is operating system?

What is an Opearting System ?

An operating system is an integrated set of specialised programs that are used to manage overall resources of and operations of the computer it is specialised software that controls and monitors the execution of all other programs that reside in the computer, including application programs and other system software.

A simple way of defining the operating system can be

An operating system is a program that acts as an interface between the user and the computer hardware and controls and manages the overall resources of Computer system.

A computer system has many resources (hardware and software) that may be required to solve a problem

According to this definition, the two primary objectives or goals of an operating system are:

1. Making a computer system convenient to use in an efficient manner

The operating systems hides the details of the hardware resources from the users and provides the users with a convenient interface for using the computer system. It acts as an intermediary between the hardware and its users and making it earsier for the users to access and use other resouces.

The hardware resources are surrounded by the operating system layer, which in turn is surrounded by a layer of other systern software (such as assemblers, compilers, interpreters, etc.) and application softwares (suh as Word processors, spread sheets, Accounting software, etc.) Finally, the users view the computer system in terms of the user interfaces provided by the operating systems.

The efficient operation of the computer system is particularly important for large, shared multiuser systems. These systems are very expensive, so it is desirable to make them as efficient as possible.

2. Managing the resources of a Computer System

This objective involves performing such tasks as keeping track of who is using which resource, granting resource requests, accounting for resource

usage and mediating conflicting requests from different programs and users. The efficient and fair sharing of resources among users and/or programs is a key goal of most operating systems.