Session 22

Session 22
Date:6.5.2010

Activities:
- Discussed about operating systems

An operating system, or OS, is a software program that enables the computer hardware to communicate and operate with the computer software. Without a computer operating system, a computer would be useless.


The main functions of an OS include:

In a multitasking operating system where multiple programs can be running at the same time, the operating system determines which applications should run in what order and how much time should be allowed for each application before giving another application a turn.

It manages the sharing of internal memory among multiple applications.

It handles and monitors input and output to and from attached hardware devices, such as hard disks, printers, and dial-up ports. [8]

It sends messages to each application or interactive user (or to a system operator) about the status of operation and any errors that may have occurred.

It can offload the management of what are called batch jobs (for example, printing) so that the initiating application is freed from this work.

On computers that can provide parallel processing, an operating system can manage how to divide the program so that it runs on more than one processor at a time.

Scheduling the activities of the CPU and resources to achieve efficiency and prevention of deadlock. [9]