COURSE: COMPUTER PLATFORMS. Topic: INTRODUCTION TO SOFTWARE AND OPERATING SYSTEMS.

COURSE:

COMPUTER PLATFORMS

Topic: INTRODUCTION TO SOFTWARE AND OPERATING SYSTEMS

OBJECTIVES

• Components of a computer system

• Interpret the basic functions of Operating System

• Files and directory structure

• Client-Server Model

• Network Operating System

COMPONENTS OF A COMPUTER SYSTEM

The computer system is basically

divided into 4 components:

1. Hardware

2. Operating System

3. Application programs

4. Users

Users

Application Programs

Operating system

Computer Hardware

ABSTRACT OVERVIEW

HARDWARE

This provides the Basic system

resources.

SYSTEM SOFTWARE

• Refers to the Operating system and all utility programs that manage computer resources at a low level.

• It includes compilers, loaders, linkers and debuggers.

APPLICATION PROGRAMS

A program or group of programs

designed for end users.

Examples: Word processing, Graphics,

Spreadsheets, Databases,

Games.

GOALS OF AN OPERATING SYSTEM

• To make the computer system convenient to use.

• To use the computer hardware in an efficient manner.

PURPOSE OF AN OPERATING SYSTEM

• The purpose of an operating system is to provide an environment in which a user may execute programs.

WHAT IS AN OPERATING SYSTEM?

• An Operating System is an interface between user and hardware of a computer system.

WHAT IS AN OPERATING SYSTEM?

• An Operating System is a system software which may be viewed as an organized collection of software consisting of procedures for operating a computer and providing an environment for execution of programs.

OTHER DEFINITIONS

• An Operating System is a control program.

• An Operating System is similar to a Government.

• An Operating System can be defined as a Resource Manager.

OTHER DEFINITIONS

• An Operating System is the layer between the H/W and the S/W

• An Operating System is a virtual computer manager

• Operating System is the first program run on a computer when the computer boots up

USER INTERFACE

A set of commands or menus through

which user communicates with the

program.

TYPES OF INTERFACES

• Command driven

• Menu driven

• Graphical user interface(GUI)

WAYS TO INTERACT WITH OPERATING SYSTEM

• OPERATING SYSTEM CALLS

• OPERATING SYSTEM COMMANDS

SYSTEM CALLS

System Calls provide the interface to a

running program and the O/S.

OPERATING SYSTEM COMMANDSUsers nay interact with the O/S directly

by means of O/S commands.

MULTIPROGRAMMING

• Multiprogramming was used as a technique to enhance the throughput efficiency.

• Overlapping interleaving computing of different jobs.

• More than one job is “ready” at the same time.

Different types of Multiprogramming Operating System

• Multitasking operating system

• Multiprocessing operating system

• Multi-user operating system

FUNCTIONS OF OPERATING SYSTEM

Memory management

Process management

Device management

Information management

Protection

Error Handling

FUNCTIONS OF OPERATING SYSTEM

Memory management

Process management

Device management

Information management

Protection

Error Handling

The o/s keeps track of the memory, what parts are in use and by whom.

FUNCTIONS OF OPERATING SYSTEM

Memory management

Process management

Device management

Information management

Protection

Error Handling

The o/s keeps track of The o/s keeps track of processors and the status processors and the status

of processes. It decidesof processes. It decides who will have a chance to who will have a chance to

use the processor.use the processor.

FUNCTIONS OF OPERATING SYSTEM

Memory management

Process management

Device management

Information management

Protection

Error Handling

The o/s keeps track of the devices,

channels, control units and decides what is an efficient way to allocate the device.

FUNCTIONS OF OPERATING SYSTEM

Memory management

Process management

Device management

Information management

Protection

Error Handling

O/S keeps track of the information, its location, use, status etc. and decides who gets use

of the resources, enforce protection requirements.

FUNCTIONS OF OPERATING SYSTEM

Memory management

Process management

Device management

Information management

Protection

Error Handling

An o/s is to protect the userAn o/s is to protect the user from unauthorized access from unauthorized access

of his files or data.of his files or data.And also it should protectAnd also it should protect

itself from usersitself from users

FUNCTIONS OF OPERATING SYSTEM

Memory management

Process management

Device management

Information management

Protection

Error Handling

An o/s must respond to errors by taking the appropriate actions.

FILE CONCEPT

File is a collection of related information.

It is named and is referred by its name.

Files are organized into directories for

easy access.

DIRECTORY STRUCTURE

ROOT D0

F1

D3D2

D21 D31

F311

F31F21

D1

D311

CLIENT-SERVER MODEL

User process(client process) sends the

request to a server process, which

when does the work and sends back

the answer.

CLIENT-SERVER ARCHITECTURE

CLIENT is an application that runs on a

personal computer or on a workstation

and relies on SERVER to perform some

operations such as managing files,

disk drives, printers or network traffic.

NETWORK OPERATING SYSTEM

The Software that enhances a basic

Operating System by adding Networking

Features.

Examples: Novell Netware, WINDOWS NT

• Operating system is an essential component of system software which consists of procedures for managing computer resources.

• Operating system functions primarily includes Memory, Process,Device, File management.