OPERATING SYSTEMS Software in the Background. Chapter 2

OPERATING SYSTEMS

Software in the Background

Objectives

• Describe the functions of an Operating System

• Explain the basics of a personal computer operating system

• Describe the advantages of a graphical operating system

• Differentiate among different versions of Microsoft Windows

• Explain the need for network operating systems

Contents

•

Operating System: Hidden Software

•

Systems Software

•

Functions of OS

•

Types of OS

• Network Operating System NOS

Operating System

Hidden Software

• Definition – provides access to all resources • Kernel

• Manages the operating system • Memory resident

• Loads set of programs that lies between applications software and the hardware

• Fundamental software that controls non-resident portions of the OS as needed

Systems Software

• Definition:

• All programs related to coordinating computer operations

• Components

• Operating System • Utility programs

Functions of OS

• Manage the computer’s resources

• CPU

• Memory • Disk drives • Printers

User Interface

• Facilitates communication between the user and

the operating system

• Two forms

• Command line

• Text-based

• Key commands

• Examples: MS-DOS, Unix

• Graphical user interface (GUI)

• Visual images • Menus

• Examples: Windows, Mac OS, Linux

Platform

• Definition:

Computer hardware and operating system software that dictate what other software can run

OS is Hidden

• User interested in application

software to make the PC

useful

• Application software is

platform specific

• User must be aware of the

type of OS

• User should be aware of the

functions of OS

Types of OS

Command line Single user PC

MS-DOS

• Command-line interface

• Prompt – system is waiting for you to do something • Key a command

Microsoft Windows

• Graphical user

interface

• Eases access to

the OS

• Most new

computers come

with Windows

already installed

GUI

• On-screen pictures

• Fast

• Easy

• Intuitive

Early Days of Windows

Operating environment for MS-DOS

Shell – layer added between users

Windows Today

• Home/consumer market

• Windows 95 • Windows 98

• Windows Millennium Edition (ME)

• Corporate market

• Windows NT • Windows 2000

• Windows XP

• Pocket computers and Internet appliances

Windows 95 and 98

• Self-contained OS

• DOS commands still available

• Start programs by

• Start button

• Double clicking the icon

• Task bar permits movement between open

programs

• Plug and play

Windows 98 Additions

• Internet / intranet browsing

• Support for DVD and additional multimedia components • Support for large hard drives

• TV viewer and broadcast ability • Wizards

Windows ME

Millennium Edition

Multimedia support -- Windows Media Player 7

• Jukebox

• Record music CDs as digital files

• Windows Movie Maker

• Basic video editing

• Windows Image Acquisition

Windows ME

Millennium Edition

• Reliability Features

• System File Protection • AutoUpdate

• System Restore

• Help Center

• Home Network Support

• Wizard for connecting multiple computers and peripherals

• Multiple users can share a single Internet connection

Windows NT

1993

New Technology

• Engineered for stability

• Strong security

• Versions

• NT Workstation • NT Server

• Drawbacks

• Lacks support for older Windows and MS-DOS software and hardware

• Complex to learn and use

Windows 2000

• Security features

• Uses simple approach to hardware setup

from Windows 98

• Versions

• Windows 2000 Professional for individual users • Windows 2000 for network servers

Windows 2000

• Complex

• Heavy demand for computer resources

• Improvements over windows NT

• Maintains user preferences

• Self-healing applications software • Supports Windows 98 file structure • Uses plug and play

Windows XP

2001

Windows 7 Windows 8 Windows 9 Windows 10

• Extends Windows ME and provides a more stable environment • Two categories

• Network server

• 3 versions based upon network complexity

• Desktop computer

• 2 versions

• Professional Client • Personal Client

Mac OS

• First commercially

successful GUI (1984)

• Mac OS X: 2000

• Served as a model to

other GUI systems

UNIX

1969

• Supports

• Multi-user

• Command-line interface

• Runs on various processors and many types of computers

LINUX

1991

• PC comes with Windows installed

LINUX

• Advantages over Windows

• Extremely stable • Internet support

• Reinstallation is simpler

• Disadvantage

Network Operating System NOS

• Designed to permit computers on a network to

share resources

• Examples

• Windows 2000 Server • Novell Net Ware

• Provides

• Data security • Troubleshooting

Functions of Utility programs

• File manager – provide access to lists of stored files • Backup and Restore – make duplicate copies of

important files and return the copy to the hard drive if needed

• Disk defragmenter – reorganize files so they are