Operating

System

Computer Seminar

os

Definition Operating system is an

interface between the user and hardware and it is also defined as one program that is running all the time in the computer

Goals Of Operating System

Execute user programs in a user

friendly atmosphere

Make computer convenient to

use

Optimize computer hardware

Types Of Operating System

Single-User Operating System

Multi-User Operating System

Single-User Operating System

This is one of the type of operating system were at a time only one user can operate the system. Example for single user operating system is Microsoft-Disk

Operating System (MS-DOS)

Multi-User Operating System

This is one of the type of operating system were more than one user can operate the system simultaneously. Example for multi-user operating system is Windows 2000, Windows Xp,Windows vista etc…….

Characters of Operating System

User Interface Memory Management Process Management File Management Networking Capabilities Management Security Management Fault Tolerance Application Base Distributed Operating System

User Interface Operating System should concentrate on the user interface. Only way that you can interact with a computer is through the user interface. The User Interface of the Operating System should be appealing to the senses. Ex: Graphical User Interface (GUI)

Memory Management

• In Memory Management any error in the user program should not be allowed to spoil the entire memory.• Operating System divides the memory into user memory and reserved memory.• If some errors creep into the user program,user memory alone gets affected however reserved memory remains in unaffected condition.

Process Management

Process Management undertakes the

allocation of processors to 1 program. Several Algorithms are used to allocate the job to the processor

FIFO (First In First Out) SJF (Shortest Job First) Round-Robin (Circular) Priority (Memory)

Security Management

The biggest challenge to Computer’s industry is to safeguard one’s data.The Operating System provides 3 levels Security to the user

(a) File Access Level(b) System Level

(c) Network Level

Fault Tolerance

Operating System should be robust.When there is a fault, the OS won’t

crash since they have fault tolerance.

Application Base

The OS should provide a solid basis for running many popular applications.

For Example,One can type a text in word pad and also hear song in a music player at the same time.

DanielRajamani 08-CS-103By