Chapter 06: System Software

Definition

Master program

Controls all hardwares connected to computer

Collection of programs

Users

Applicationsoftware

Applicationsoftware

OperatingSystem/systemsoftware

OperatingSystem/systemsoftware

Hardware

System Software/Operating Systems

Operating Systems

A collection of programs that handle technical tasks, including managing computer resources

Every computer has an operating system (OS), such as Windows 7 or Mac OS X

The OS provides the interface between the user and computer, and is required to run applications

Functions of an Operating System

Manages computer resources Coordinate memory, processing storage, and printers

Monitor system performance

Provide security

Start-up the computer

Provides user interface Character-based interface

Graphical user interface (GUI)

Runs applications Multitasking

Foreground and background applications

Program Interface

Humans

User Programs

O.S. Interface

O.S.

Hardware Interface/ Privileged Instructions

Disk/Tape/Memory

The Layers Of A System System

Layers of System Software

Booting

Booting is the process of bringing OS from Hard disk to RAM

Categories of Operating Systems

Hundreds of operating systems

Three basic categories

Embedded operating systems (handheld)

Network operating systems (linked computers)

Stand-alone operating systems (desktop)

Storage Hierarchy

Very fast storage is very expensive. So the Operating System manages a hierarchy of storage devices in order to make the best use of resources. In fact, considerable effort goes into this support.

1: Operating Systems Overview 10

Fast and Expensive

Slow an Cheap

Operating System - Properties

1. Batch processing

Mr. Mohammed Rahmath

Operating System - Properties

2. Multitasking

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Operating System - Properties

3. Multiprogramming

Mr. Mohammed Rahmath