Computer Fundamental by Goel Anita

C o m p u te r F u n d a m e n ta ls

Copyright © 2010 Dorling Kindersley (India) Pvt. Ltd

This book is sold subject to the condition that it shall not, by way of trade or otherwise, be lent, resold, hired out, or otherwise circulated without the publisher’s prior written consent in any form o f binding or cover other than that in which it is published and without a similar condition including this condition being imposed on the subsequent purchaser and without limiting the rights under copyright reserved above, no part of this publication may be reproduced, stored in or introduced into a retrieval system, or transmitted in any form or by any means (electronic, mechanical, photocopying, recording or otherwise), without the prior written permission of both the copyright owner and the above-mentioned publisher o f this book. ISBN 978-81-317-3309-7 10 9 8 7 6 5 4 3 2 1 Published by Dorling Kindersley (India) Pvt. Ltd., licensees of Pearson Education in South Asia Head Office: 7th Floor, Knowledge Boulevard, A-8 (A), Sector 62, NOIDA, 201 309, UP, India. Registered Office: 11 Community Centre, Panchsheel Park, New Delhi 110017, India Typeset by AcePro India Pvt. Ltd Printed in India at Saurabh Printers Pvt. Ltd. Copyrighted material

B r ie f C o n t e n t s Preface

xxi

Acknowledgem ents

XXV

UNIT 1 BASiCS_OF_COMPUIER 1. Introduction to Computer 2. The Computer System Hardware 3. Computer Memory 4. Input and Output Devices 5. Data Representation

1 19 39 61 87

UNIT II USER-COMPUTER INTERFACE 6. Interaction of User and Computer 7. Operating System 8. Computer Programming Fundamentals 9. Data Communication and Computer Network 10. The Internet and Internet Services

115 131 150 163 196

UNIT 111 APPLICATIONS AND SECURITY 11. Information Systems 12. Fundamentals of Database 13. Multimedia 14. Computer Security

219 236 256 284

UNIT IV COMPUTER PRACTICALS 15. Windows XP 16. MS-Word 2007 17. MS-Excel 2007 18. MS-PowerPoint 2007 19. MS-Access 2007 20. Network and Internet Connections 21. Using LaTeX

307 342 379 422 458 486 503

•

Appendix A Appendix B Appendix C Appendix D Index

515 517 519 523 541

Copyrighted material

Contents rretace Acknowledgements 1JN 1 T 1

XXI XXV

R A S IC S O F T O M P I J T F R

1

1. Introduction to Computer

1

1.1 Introduction

1

1.2 Digital and Analog Computers

2

1.3 Characteristics of Computer

2

1.4 History of Computer

3

1.5 Generations of Computer

4

1.5.1 1.5.2 1.5.3 1.5.4 1.5.5

First Generation (1940 to 1956): Using Vacuum Tubes Second Generation (1956 to 1963): Using Transistors Third Generation (1964 to 1971): Using Integrated Circuits Fourth Generation (1971 to present): Using Microprocessors Fifth Generation (Present and Next): Using Artificial Intelligence

1.6 Classification of Computer 1.6.1 1.6.2 1.6.3 1.6.4

Microcomputers Minicomputers Mainframe Computers Supercomputers

1.7 The Computer System 1.7.1 The Input-Process-Output Concept 1.7.2 Components of Computer Hardware

1.8 Application of Computers

4 5 5 6

6 7 7 9 9 9 10 11 12

13

Summary

15

Keywords

16

Questions

17

2, The Computer System Hardware

19

2.1 Introduction

19

2.2 Central Processing Unit

20

2.2.1 Arithm etic Logic Unit 2.2.2 Registers 2.2.3 Control Unit

20 21 22


_______ v iii I.

1 Contents

2.3 Memory Unit 2.3.1 Cache Memory 2.3.2 Primary Memory 2.3.3 Secondary Memory

22 22 n 24

2.4 Instruction Format

24

2.5 Instruction Set

25

2.6 Instruction Cycle

25

12. Microprocessor

22

13. Interconnecting the Units of a Computer

21 28 29 29

2.8.1 System Bus 2.8.2 Expansion Bus 2.8.3 External Ports

2.9 Performance of a Computer 2.10 Inside a Computer Cabinet 2.10.1 2.10.2 2.10.3 2.10.4 2.10.5 2.10.6 2.10.7

Motherboard Ports ancf Interfaces Expansion Slots Ribbon Cables Memory Chips Storage Devices Processor

29

31 31 32 12

31 34 34 34

Summary

35

Keywords

36

Questions

36

Computer Memory

39

3.1 Introduction

39

3.2 Memory Representation

40

3.3 Memory Hierarchy

40

3.4 CPU Registers

42

3.5 Cache Memory

42

3.6 Primary Memory

43

3.6.1 Random Access Memory 3.6.2 Read O nly Memory

43 44

3.7 Secondary Memory

46

3.8 Access Types of Storage Devices

46

3.8.1 Sequential Access Devices 3.8.2 Direct Access Devices

3.9 Magnetic Tape

46 47

47 Copyrighted material

Contents

j

3.10 Magnetic Disk

IX

48

3.10.1 Floppy Dink_________________________________________________________ 50 lJQ.2-Bnr.cLDi±k____________________________________________________ i I 3.10.3 Zip Disk______________________________________ .______________________ 52

3.11 Optical Disk__________________________________________________ 52 3.11.1 CD-R O M ________________________________________________ 51 ±J±2-DYDzRQM __________________________________________________________ 51 3.11.3 Recordable O ptical Disk 55

3.12 Magneto-Optical Disk

55

3.13 Using the Computer Memory___________________________________ 56 Summary_____________________________________________________ 56 Keywords_____________________________________________________ 57 Questions_____________________________________________________ 58

}

4. Input and Output Devices__________________________________________ 6

4J._lntiQ .duc.ti.Q n________________________________________________________________ 6 J

Input-Output Unit

62

4.2.1 Input Unit 4.2.2 Output Unit

62 62

4.3

Input Devices

63

4.4

Human Data Entry Devices

64

4.2

4.4.1 Keyboard 64 4.4.2 Pointing Devices______________________________________________________ 65 4.4 J L l_MQii.se__________________________________________________________(15 4.4.2.2 TrackBali 66 4.4.2.3 joystick 66 4.4.2.4 Digitizing Tablet 67

4.4.3 Pick Devices

68

4.4.3.1 Light Pen 4.4.3.2 Touch Screen 4.5

68 68

Source Data Entry Devices_____________________________________

69

4 .5 .1 A u d io In p u t D e v ic e _________________________________________________________ 6 9

4.5.2 Video Input Device___________________________________________________ 69 4.5.3 O ptical Input Devices 70 4.5.3.1 4.5.3.2 4.5.3.3 4.5.3.4 4.5.3.5 4 .6

Scanner Optical Character Recognition (OCR) Magnetic Ink Character Recognition (MICR) Optical Mark Recognition (OMR) Barcode Reader

Output Devices 4.6.1 Hard Copy Devices 4.6.1.1 Printer 4.6.1.2 Plotter 4.6.1.3 Computer Output on Microfilm

70 71 72 72 72 74

74 74 76 77 Copyrighted material

—

M g

Contents

4.6.2 Soft Copy Devices 4.6.2.1 4.6.2.2 4.6.2.3 4.6.2.4

77

Monitor Visual Display Terminal Video Output Audio Response

77 77 78 78

4.7 I/O Port

80

4.8 Working of I/O System Summary Keywords Questions

81 82 83 84

5. Data Representation

87

5.1 Introduction

87

5.2 Number System

88

5.2 .1 Decim al Number System 88 5.2.2 Binary Number System _______________________________________________ 89 5.2.3 O ctal Number System________________________________________________ 89 5.2.4 Hexadecimal Number System________________________________________ 89

5.3 Conversion from Decimal to Binary, Octal, Hexadecimal 5.3. / Converting Decim al Integer to Binary, Octal, Hexadecimal 5.3.2 Converting Decim al Fraction to Binary, Octal, Hexadecimal 5 .3 .3 C o n ve rtin g D e c im a l Integer. Fraction to B inary, O c ta l,

90

90 92

Hexadecimal

94

5.4 Conversion of Binary, Octal, Hexadecimal to Decimal

95

5.5 Conversion of Binary to Octal, Hexadecimal

97

5.6 Conversion of Octal, Hexadecimal to Binary

97

5.7 Binary Arithmetic

98

5.7.1 Binary Addition 5.7.2 Binary Subtraction

98 100

5.8 Signed and Unsigned Numbers

102

5.8.1 Complement of Binary Numbers

102

5.9 Binary Data Representation

103

5.9 .1 Fixed Point Number Representation

103 105

5.9.2 Floating Point Number Representation

5.10 Binary Coding Schemes

106

5.10.1 EBCDIC 106 5.10.2 A SC II_________________________________________________________ 106 5^1D,3.JJniL0ik ____________________________________________________________ W Z

5.11 Logic Gates__________________________________________________ Summary Keywords Questions Answers

108 110 110 111 113


Contents

UNIT II

USER-COMPUTER INTERFACE

6. Interaction of User and Computer

I Ix i 115 115

6.1 Introduction

115

6.2 Types of Software

116

6.3 System Software

116

6.3.1 6.3.2 6.3.3 6.3.4

Operating System Device Driver System Utilities Programming Languages

117 117 118 120

6.3.4.1 Machine Language 6.3.4.2 Assembly Language 6.3.4.3 High-level Language 6.3.4.4 Different Generations of Programming Languages

121 121 122 122

6.3.5 Translator Software 6.3.5.1 Assembler 6.3.5.2 Compiler 6.3.5.3 Interpreter

6.3.6 Linker 6.3.7 Loader

122 124 124 125

125 125

6.4 Application Software

126

6.5 Software Acquisition Summary Keywords Questions

127 128 129 129

7. Operating System

131

7.1 Introduction

131

7.2 Objectives of Operating System

132

7.3 Types of OS

132

7.4 Functions of OS

134

7.5 Process Management

135

7.5.1 CPU Scheduling 7.5.2 Process Synchronization 7.5.3 Deadlock

7.6 Memory Management 7.6.1 Memory Allocation 7.6.2 Virtual Memory

136 136 137

138 138 139

7.7 File Management

140

7.8 Device Management

141

7.9 Protection and Security


Contents

7.10 User Interface

143

7.11 Examples of Operating Systems

144

7.11.1 MS-DOS 7.11.2 Windows Family of OS 7.11.2.1 Brief History of Windows OS

144 145 146

7.11.3 Linux OS

146

Summary

147

Keywords

147

Questions

148

Computer Programming Fundamentals

150

8.1 Introduction

150

8.2 Program Development Life Cycle

151

8.3 Algorithm

152

8.4 Control Structures

153

8.5 Flowchart

153

8.5.1 Flowchart Symbols

8 .5 .2 P re p a rin g a F lo w c h a rt 8.6 Pseudo Code 8.6.1 Preparing a Pseudo Code

8.7 Programming Paradigms

153

153

156 156

158

8.7.1 Structured Programming 8.7.2 Object-Oriented Programming (O O P) 8.7.3 Aspect-Oriented Programming

158 159 160

Summary

161

Keywords

161

Questions

162

Data Communication and Computer Network

163

9.1 Introduction

163

9.2 Importance of Networking

164

9.3 Data Transmission Media

165

9.3.1 9.3.2 9.3.3 9.3.4 9.3.5 9.3.6

Twistedpair Coaxial Cable O ptical Fiber Radio Transmission Microwave Transmission Satellite Transmission

765 766 766 767

168 168 Copyrighted material

Contents

1____ x iil

9.4 Data Transmission Across Media

168

9.4.1 Transmission Modes 9.4.2 Transmission Speed 9.4.3 Fundamentals o f Transmission

168 170 170

9.4.3.1 Analog and Digital Signals 9.4.3.2 Modulation and Demodulation 9.4.3.3 Multiplexing 9.4.3.4 Asynchronous and Synchronous Transmission

9.5 Data Transmission and Data Networking 9.5.1 Switching 9.5.1.1 Circuit Switching 9.5.1.2 Message Switching 9.5.1.3 Packet Switching

171 172 174 174

175 176 177 177 177

9.6 Computer Network

178

9.6.1 Network Types

178

9.6.1.1 Local Area Network 9.6.1.2 Metropolitan Area Network 9.6.1.3 W ide Area Network 9.6.2 LAN Topologies 9.6.2.1 Bus Topology 9.6.2.2 Ring Topology 9.6.2.3 Star Topology 9.6.3 Communication Protocol

9.6.4 Network Devices 9.6.4.1 9.6.4.2 9.6.4.3 9.6.4.4 9.6.4.5 9.6.4.6 9.6.4.7

Network Interface Card Repeater Bridge Hub Switch Router Gateway

9.7 Wireless Networking

179 179 180

180 180 181 181

181 184 184 185 186 186 187 188 188

189

9.7.1 Bluetooth Technology 9.7.2 Wireless LAN 9.7.3 Wireless W AN

189 190 191

Summary

192

Keywords

193

Questions

193

10. The Internet and Internet Services

196

10.1 Introduction

196

10.2 History of Internet

197

10.3 Internetworking Protocol

198

10.4 The Internet Architecture

198

■ B x iv H il

Contents

10.5 Managing the Internet

199

10.6 Connecting to Internet

199

10.7 Internet Connections

200

10.7.1 10.7.2 10.7.3 10.7.4 10.7.5

Dial-up Access Leased Line Integrated Services Digital Network (ISD N ) Digital Subscriber Line (D SL) Cable Modem

201 201 202 202 203

10.8 Internet Address

203

10.9 Internet Services

204

10.9.1 World W ide Web (W W W ) 10.9.1.1 W ebBrowser 10.9.1.2 Uniform Resource Locator (URL) 10.9.1.3 Internet Search Engines 10.9.1.4 W W W Development Languages

204 206 207 207 209

10.9.2 Electronic M ail

210

10.9.2.1 10.9.2.2 10.9.2.3 10.9.2.4

210 210 211 211

E-mail Address E-mail Message Format E-mail Services How E-mail Works

10.9.3 File Transfer Protocol (FTP) 10.9.3.1 How FTP Works

10.9.4 Terminal Network (Telnet) 10.9.5 News 10.9.6 Internet Relay Chat (IR C )

212 213

213 214 214

10.10 Uses of Internet

214

Summary

215

Keywords

216

Questions

216

UNIT III

APPLICATIONS AND SECURITY

11.

219 Information Systems219

11.1 Introduction

219

11.2 Data, Information and Knowledge

220

11.3 Characteristics of Information

221

11.4 Information System (IS)

221

11.5 Computer-Based Information System (CBIS)

223

11.6 Need for Efficient Information System

224

11.7 Categories of Information System


Contents

11.8 Operations Support System 11.8.1 Transaction Processing System (TPS) 11.8.2 Office Automation System (O A S)

11.9 Management Support System 11.9.1 Management Information System (M IS) 11.9.2 Decision Support System (D SS) 11.9.3 Executive Information System (EIS)

11.10 Specialized Information System 11.10.1 Expert Systems 11.10.2 Enterprise Resource Planning (ERP) 11.10.3 Electronic-Commerce (E-Commerce)

11.11 Careers in Information Systems

i 1 -'IBfeSSlliS

226 226 227

228 228 229 230

230 230 231 231

232

Summary

233

Keywords

234

Questions

234

Fundamentals of Database

236

12.1 Introduction

236

12.2 Database

237

72.2.1 File-Oriented Approach and Database Approach

12.2.2 Characteristics of Database Approach 12.2.3 Data Models, Schema and Instances 12.2.4 High-Level or Conceptual Data M odel 12.2.4.1 12.2.4.2 12.2.4.3 12.2.4.4

Entity Attribute Relationship Entity-Reiationship (E-R) Model

12.2.5 Representation or Implementation Data M odel 12.2.5.1 Relational Database Model 12.2.5.2 Hierarchical Database Model 12.2.5.3 Network Database Model

12.2.6 Low-Level or Physical Data M odel

12.3 Database System 12.3.1 Components of Database System 12.3.2 Architecture o f Database System

237 239 240 240 240 240 241 241

242 242 244 244

245

245 245 246

12.4 Database Management System________________________________ 247 12.4.1 12.4.2 12.4.3 12.4.4

Data Independence________________________________________________ 248 Data Dictionary____________________________________________________ 248 Database Administrator (D BA )____________________________________ 249 Database Languages_______________________________________________ 249 12.4.4.1 Data Definition Language (DDL)_____________________________ 249 12.4.4.2 Data Manipulation Language (DML)__________________________ 249


_________ XVI

1 Contents

12.5 Database System Architectures 12.5.1 Centralized D BM S Architecture 12.5.2 Client-Server Architecture 12.5.3 Distributed Databases

12.6 Database Applications

250 250 250 251

251

Summary

252

Keywords

253

Questions

253

13. Multimedia

256

13.1 Introduction

256

13.2 Multimedia: Definition

257

13.3 Characteristics of Multimedia System

257

13.4 Elements of Multimedia

259

13.4.1 Text 13.4.2 Graphics

*

13.4.2.1 Bitmap Graphics 13.4.2.2 Vector Graphics

13.4.3 Audio 13.4.3.1 Audio from a CD to W eb

13.4.4 Video 13.4.4.1 Video on Internet

13.4.5 Animation

13.5 Multimedia System 13.5.1 Desirable Features of Multimedia System

13.6 Multimedia Applications 13.6.1 13.6.2 13.6.3 13.6.4 13.6.5

In Education In Entertainment In Training In Business Virtual Reality

259 260 262 264

265 266

268 269

271

272 272

273 273 276 277 277 278

Summary

280

Keywords

280

Questions

281

14. Computer Security

284

14.1 Introduction

284

14.2 Security Threat and Security Attack

285

14.3 Malicious Software

286

14.3.1 Virus 14.3.2 Worms


Contents

14.3.3 Trojan Horses 14.3.4 Javascripts, Java Applets and ActiveX Controls

14.4 Hacking 14.4.1 Packet Sniffing 14.4.2 Password Cracking 14.4.3 E-mail Hacking

X V Ii

287 288

288 289 289 289

14.5 Security Services

289

14.6 Security Mechanisms

290

14.7 Cryptography

290

14.7.1 Secret Key Cryptography 14.7.2 Public-Key Cryptography 14.7.3 Hash Functions

291 291 292

14.8 Digital Signature

292

14.9 Firewall

294

14.9.1 Types of Firewall 14.9.1.1 Packet Filter Firewall 14.9.1.2 Circuit Filter Firewall 14.9.1.3 Application-Level Gateway

14.10 Users Identification and Authentication 14.10.1 User Name and Password 14.10.2 Smart Card 14.10.3 Biom etric Techniques

UNIT IV

|

2 96 296 296 297

297 298 299 299

14.11 Other Security Measures

300

14.12 Security Awareness

301

14.13 Security Policy

302

14.13.1 Formulating a Security Policy

302

Summary

303

Keywords

304

Questions

304

COMPUTER PRACTICALS

15.

307 Windows XP

15.1 Introduction

307

15.2 Features of Windows XP

308

15.3 The Desktop

308

307

L5 A J.-Ih eJzsk.Bar.________________________________________________________ m IJAJJ^.kilcQiis.d.Dd.Sh.QrLcu.ts____________________________________________111

15.4 Structure of Windows


-Triii

I Contents

15.5 Windows XP Explorer 15.5.1 15.5.2 15.5.3 15.5.4 15.5.5 15.5.6

The Start The Window The View Selecting Files Working with Folders Files and Folders Properties

314 314 315 316 317 317 318

15.6 The Search

323

15.7 The Recycle Bin

323

15.8 Configuring the Screen

324

15.9 Configuring the Mouse

326

15.10 Adding or Removing Programs

328

15.11 Adding New Hardware

328

15.12 System Tools

330

15.13 The Scandisk

332

15.14 Windows XP Media Player

334

15.15 Windows XP Help

334

15.16

334

W in d o w s V ista

15.17 Windows 7 Questions

Word 2007

337 340

342

16.1 Introduction

342

16.2 Starting MS-Word

343

16.3 MS-Word Screen and Its Components

344

16.4 The Office Button

347

16.5 The Ribbon

350

16.5.1 16.5.2 16.5.3 16.5.4 16.5.5 16.5.6 16.5.7 16.5.8

353 355 358 360 360 363 365 3 66

The Home Tab The Insert Tab The Page Layout Tab The References Tab The Mailings Tab The Review Tab The View Tab The Help

16.6 Solved Examples Exercises


Contents

|

379

MS-Excel 2007 17.1 Introduction

379

17.2 Start MS-Excel

380

17.3 Basics of Spreadsheet

381

17.4

MS-Excel Screen and Its Components

382


386

17.6 The Ribbon

390

77.6.7 The Home Tab

392

17.6.2 17.6.3 17.6.4 17.6.5 17.6.6 17.6.7 17.6.8

394 399 400 403 405 406 408

The The The The The The The

Insert Tab Page Layout Tab Formulas Tab Data Tab Review Tab View Tab Help

17.7 Solved Examples Exercises

409 417

MS-PowerPoint 2007

422

18.1 Introduction

422

18.2 Basics of PowerPoint

424

18.3 Start MS-PowerPoint

425

18.4 MS-PowerPoint Screen and Its Components

426

18.5 The Office Button 18.6 The Ribbon

429 434

18.6.1 18.6.2 18.6.3 18.6.4 18.6.5

The Home Tab The Insert Tab The Design Tab The Animations Tab The Slide Show Tab

18.6 .6 T he R e v ie w Tab

18.6.7 The View Tab 18.6.8 The Help

18.7 An Example Exercises

MS-Access 2007

435 438 440 442 443 446 447 452

453 456

458

19.1 Introduction

458

19.2 Database Terminology

459

19.3 Start MS-Access

460 py righted

H

B

H

1

Contents

19.4 MS-Access Screen and Its Components

461


463

19.6 The Ribbon

467

19.6.1 19.6.2 19.6.3 19.6.4 19.6.5

The Home Tab The Create Tab The External Data Tab The Database Tools Tab The Help

468 472 475 476 477

19.7 Solved Example

478

Exercises

483

20. Network and Internet Connections

486

20.1 Introduction

486

20.2 Start Network Connections

487

20.3 Create a New Connection

488

20.4 Manage a Network Connection

491

20.5 Network Setup

493

20.6 Windows Firewall

493

2 0 .7

495

S h a rin g o f File s

20.8 Wireless Network Setup

496

20.9 Connect using Virtual Private Network (VPN)

497

20.10 Set Up a Wired Network

498

20.11 Automatic Wireless Network Connections

498

20.12 Set up Internet Properties— Internet Options

501

20.13 Choose an Internet Connection

502

21. Using LaTeX

503

21.1 Introduction

503

21.2 Create LaTeX Document

504

21.3 Components of a LaTeX Document

504

21.4 LaTeX Commands

504

21.5 Solved Examples

508

Exercises Appendix Appendix Appendix Appendix

514 A B C D

515 517 519 523

Index________________________________________________________ 5A1 Copyrighted mate

P

r e f a c e

C om puters play a key role in o u r everyday lives. In addirion co com m unication m edia like television, radio and newspaper, we now have another com m unication m edium , i.e. com puters. We use com puters to e-m ail, to chat, for the Internet browsing, for teleconferencing, for video conferencing, etc. W e also use them for e-learning, e-com merce, e-banking, e-governance, e-ticketing and for m any m ore things. And the interesting part is, while we interact w ith the other m edia like television, radio, newspaper, etc. to merely get inform ation, the interaction in com puters is tw o ways— we can be a creator as well as a user. We m ay use a com puter as a m edium to get m ore inform ation, as a tool to perform certain activities, o r as an integral part o f another com ponent. T h e fundam entals o f com puters arc the stepping stones to com puter science. Nowadays, all courses, related and unrelated to com puter science, require using a com puter. Knowledge o f the basics o f co m p u t ers has becom e a fundam ental requirem ent, in whatever area we choose to study o r follow professionally. C o m p u ter fundam entals are also an introductory course to a m ore advanced study o f com puter science.

ABOUT THE BOOK T his book is w ritten w ith the aim o f introducing the fundam entals o f com puters to the reader. A ttention has been paid to include chapters that are required by the students studying different courses. T h e book deals w ith b o th the theoretical concepts and the p rac tic a l. T h e unique features o f this book are as follows:

0

Style o f W riting • T h e language used in the book is lucid, is easy to understand, and facilitates easy grasping o f • • •

• • •

concepts. T h e chapters have been logically arranged in sequence. T h e book is w ritten in a reader-friendly m anner both for the students and the teachers. M ost o f the content presented in the book is in the form o f bullets, organized sequentially. This form o f presentation, rather than in a paragraph form , facilitates the reader to view, understand and rem em ber the points better. T h e explanation is supported by diagrams, pictures and images wherever required. Sufficient exercises have been included for practice in addition to the solved examples. T h e questions at the end o f the chapter are given section-wise. It is easier for the reader to find answers for the section-wise questions in a particular section rather than the whole book.

(♦) Content o f Book — Theory (Chapters 1 -1 4 ) • Several latest topics have been included in the book. Some o f these topics are ■ USB, Z ip disk, Flash m em ory

■ Wireless networking ■ N otebook, N etbook, PDA, sm artphones ■ Aspect O riented Program m ing (AOP) ■ Im parting education via m ultim edia ■ Cryptography, Digital signature, Firewall, Biometrics ■ System clock, BIO S, C M O S , SIM M & D IM M m em ory m odule • In the theory chapters (Chapters 1-14), the theory is supported with the practical information like, the nam e o f supercom puter o f India, how to create m p3 file from C D , w hat is a stream ing video and understanding m achine configuration.


XXli

1 Preface • T his book does not discuss in detail the old technologies that have becom e too com m on o r are no longer used, like, about keys in a keyboard, m agnetic tape, using mouse, drum printers and message switching. • Several colored inserts in the book provide a colored view o f the photographs.

0

Content o f Book—Practical (Chapters 15-21) a n d Appendix • T his book describes MS-Office with the latest com m ercially available version, version 2007. • T his book includes description o f Windows Vista and Windows 7 in addition to the detailed description o f W indow s XP. • T h e solved examples in the M S-O ffice chapters arc described step-wise. • A long list o f practical exercises is provided at the end o f each chapter. • Some chapters contain topics that are new to a book on com puters. These chapters are ■ C hapter 11— Inform ation Systems ■ C hapter 12— Fundam entals o f Database ■ C hapter 14— C om puter Security ■ C hapter 19— MS-Access ■ C hapter 20— N etw ork and Internet C onnections ■ C hapter 21— Using LaTeX ■ Appendix D — Assembling a PC.

TARGET AUDIENCE This book has been w ritten keeping in m ind the readers familiar and not-so familiar w ith com puters. Several chapters have been included that cover the syllabi of different universities in India. T h e book is well suited for the following target audience: 0

Computer science students undergoing a course in com puter science— D C A , M CA, BSc(Gcn), BSc(Hons), M Sc(IT), BSc(IT), BCA, D O E A C C level courses.

0

Engineering students of first year— BTech, BE.

0

Science students pursuing BSc in physics, chemistry, botany, zoology and mathematics.

0

Non-science students pursuing B C om (P), B C om (H ons), BA(P), BDP, BBA, MBA, BBE

0

Students enrolled in short-term courses on I T in polytechnics, training institutes, Technical Institutes.

0

Any learner interested in com puter science.

STRUCTURE OF THE TEXT T h e book follows a structured and m odular design, to facilitate the instructor in the teaching o f the course and the students in the reading o f rhe book. Figure 1 shows the design o f the book. T h e following para graphs present a brief review o f the four units o f the book. U nit I comprises five chapters. T his unit introduces the reader to the computer as a machine. C hapter 1 provides a b rief introduction to com puters— their evolution, types and applications. C hapter 2 discusses organization o f the com puter, different parts inside a com puter case and their interaction. C hapter 3 provides an overview o f the m em ory hierarchy, different kinds o f m em ory o f the com puter and storage devices that are required for storing large quantities o f data. T he different devices that are used for providing input to the computer, and the presentation o f o u tp u t from the com puter are discussed in C hapter 4. T he com puter uses the binary num ber system; C hapter 5 discusses binary coding schemes, logic gates, and the representation and conversion o f num bers in the binary, octal and hexadecimal num ber system. Copyrighted mati

Preface

Figure 1

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Modular structure of text

U nit II comprises five chapters. T his unit focusses on the interaction o f user and computer, and the Internet. C hapter 6 provides a description o f the system software and the application software. C h ap ter 7 describes the operating system in detail. T he writing o f the program m ing logic and the different program m ing para digms are discussed in C hapter 8. Chapters 9 and 10 relate to networking and the Internet. C hapter 9 discusses com puter networks and the com m unication o f data across the network. T h e Internet and its services are detailed in C hapter 10. U nit III contains four chapters. This unit is about applications and security. C hapter 11 describes the inform ation systems. This chapter is included bearing in m ind the non-science courses. For teaching this paper in a science course, you may skip this chapter. T he fundam entals o f databases are discussed in C hapter 12. C hapter 13 describes the different elements o f the m ultim edia system— text, audio, graphics, video and anim ation. C hapter 14 on com puter security discusses the security attacks, and the way to handle them. Unit IV consists o f seven chapters. This unit is designedfor the computer practicals. A detailed discussion on W indow s XP is provided in C hapter 15, including a brief description about W indow s Vista and W indow s 7. C hapters 16 through 19 are about the four m ain com ponents o f M S-Office 2007, i.e. M S-W ord, M S-Excel, M S-Pow erpoint and MS-Access. C hapter 20 is about N etw ork and the Internet connections. T h is chapter facilitates the reader in the creation and m anaging o f com puter netw ork and the Internet connection. C hapter 21 is about using LaTeX which is used for the production o f publication-quality typeset docum ents.

PEDAGOGICAL FEATURES Pedagogy is the art and science o f how som ething is taught and how students learn it. H ow the teaching occurs, the approach to teaching and learning, the way the co n ten t is delivered and w hat the students learn as a result o f the process are all included in pedagogy. T he following are the pedagogical features in this book: ® S ta rt-o f Chapter Aids • C ontents— An overall view o f the topics discussed in the chapter is provided, at the beginning o f each chapter. • W hy this chapter— It describes the need o f including this chapter in com puter fundam entals and w hy one should read it. ® In-Between Chapter A ids • Visualization— “A picture is w orth a thousand words” is a famous quote. T his book supports the concepts w ith figures, diagrams and images to facilitate visualization. • Bulleted text— T he book follows a bulleted approach o f w riting the text in contrast to the long paragraphs. T h e bulleted text approach is easier to read, understand and grasp. Copyright

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1 P re fa c e

® End-of-Chapter Aids • Sum m ary— Ir reviews the m ajor concepts discussed in the chapter. • Keywords— A list o f keywords at the end o f each chapter facilitates in locating a topic in the chapter. • Q uestions— T h e questions at the end o f each chapter are given section-wise. T h e reader has to search for the answers in this section, rather than the com plete chapter. • Extra questions— A t the end o f each chapter, the extra questions from the com plete chapter are given in th e form o f short notes, abbreviations and differences. • Colored inserts— A first initiative in a book on this topic, the colored inserts provide the reader w ith actual images in colour.

FEEDBACK For interacting with the author, or for suggestions and com m ents on this book, please send your e-mails at goel.anita.book^gm ail.com .


A

c k n o w l e d g e m e n t s

It took me alm ost 2 years to write this book. D uring m y journey o f book w riting, I have been helped and supported by m y family, friends and collegues. 1 express my gratitude to one and all for their extensive support in this endeavour. I am grateful to Dr. S. C . G upta, Prof. S. K. Wasan and Dr. M ukul Sinha for encouraging me to write a book. I thank them for their valuable advice and for their encouragem ent to dissem inate inform ation. I also th an k them for continually inspiring m e to w rite a good book. I th an k M r Neeraj Saxena, Ms Renu Saxena and M r Rajendra for their extensive help in clicking the photographs in this book. M y special thanks go to all my students, A m it Jain in particular, who have always been eager to inform m e the the expectations o f the students o f a book. T h eir suggestions and feedback have helped m e write the book in a student-friendly manner. T hanks to M r Sachin Saxena and the team o f Pearson Education for their extensive support. T h e book in its present form is a result o f the long discussions and the brainstorm ing sessions w ith Sachin. I am grateful to Sachin for his ideas, suggestions and excellent support provided to m e during the w riting o f this book. I express m y regards and love to m y m other Urm ila, and m y father Am ar C hand. Being their child makes me feel special, and I thank them both for guiding m e through life. T h ro u g h this book. I carry forward the legacy o f book w riting from m y m aternal grandfather late M r C . S. Jain. I express m y respect and thanks to m y father-in-law Gopal Krishan for his m otivation and cooperation, and for taking care o f m atters while I was busy w riting the book. M y thanks are due, in m em ory of m y m other-in-law Pushpa w ho has always loved and supported me. T hanks to m y loving husband, Ajay, for standing by m e in the difficult times d u rin g the course o f w rit ing this book. H e is a bagful o f innovative ideas and has contributed creatively to the w riting o f this book. M y special thanks to my lovely and beautiul children, A nirudh and Ashima, who brilliantly contributed towards the creation and editing o f this book. T hey are m y greatest source o f inspiration and m otivation. Since this is n o t the first book on this topic, I thank the authors o f other books on sim ilar topic, whose books have been a source o f ideas for me. I th an k the A lm ighty w ithout whose grace it w ould have been impossible for m e to accomplish this task.


Unit I

BASICS OF COMPUTER

INTRODUCTION TO COMPUTER ® ® ®

©

Digital and analog computers Characteristics of computer— Speed, accu racy, diligence, storage capability, versatility History of computer— Calculating machines, Napier's bones, slide rule, Rascal's adding and subtraction machine, Leibniz's multiplication and dividing machine, punch card system, Babbage's analytical engine, Hollerith's punched card tabulating machine Generations of computer • First generation (1940 to 1956): Using vacuum tubes • Second generation (1956 to 1963): Using transistors • Third generation (1964 to 1971): Using integrated circuits • Fourth generation (1971 to present): Using microprocessors • Fifth generation (present and next): Using artificial intelligence

©

® ® ®

®

Classification of computer— Micro computers (desktop computer or Personal Computer (PC), notebook computers or laptop, netbook, tablet computer, handheld computer or Personal Digital Assistant (PDA), smart phones), minicomputers, mainframe computers, supercomputers The computer system— Hardware, software, data, users The Input-process-output concept Components of computer hardware— Input/output unit, central processing unit, storage unit Application of computers— Education, en tertainment, sports, advertising, medicine, science and engineering, government, home

W h y this chapter

Com puters are an integral part of our lives. W h e re ve r w e are— sitting in our homes, w ork ing in the office, driving on roads, sitting in a m ovie hall, staying in a hotel, etc.— our lives are directly or indirectly affected by the com puters. In this era of inform ation, w e are dependent on the storage, flow and processing of data and inform ation, w hich can o n ly be possible w ith the help of com puters. The purpose of this chapter is to introduce you to the "com puter".

1.1 INTRODUCTION Nowadays, com puters are an integral part o f our lives. T hey are used for the reservation o f tickets for airplanes and railways, paym ent o f telephone and electricity bills, deposit and w ithdraw al o f m oney from banks, processing o f business data, forecasting o f weather conditions, diagnosis o f diseases, searching

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Basics of Computer

for inform ation on the Internet, etc. C om puters are also used extensively in schools, universities, organiza tions, m usic industry, movie industry, scientific research, law firms, fashion industry, etc. T h e term com puter is derived from the w ord compute. T h e w ord compute means to calculate. A com puter is an electronic m achine that accepts data from the user, processes the data by perform ing calcula tions and operations on it, and generates the desired o u tp u t results. C o m p u ter perform s both simple and complex operations, with speed and accuracy. This chapter discusses the history and evolution o f com puter, the concept o f input-process-output and the characteristics o f com puter. T his chapter also discusses the classification of digital com puters based on their size and type, and the application o f com puter in different dom ain areas.

1.2 DIGITAL AND ANALOG COMPUTERS A digital computer uses distinct values to represent the data internally. All inform ation are represented using the digits Os and Is. T he com puters that we use at our hom es and offices are digital com puters. Analog computer is another kind o f a com puter that represents data as variable across a continuous range o f values. T h e earliest com puters were analog com puters. Analog com puters are used for m easur ing o f param eters that vary continuously in real tim e, such as tem perature, pressure and voltage. Analog com puters m ay be m ore flexible bur generally less precise than digital com puters. Slide rule is an example o f an analog com puter. T h is book deals only w ith the digital computer and uses the term computer for them .

1.3 CHARACTERISTICS OF COMPUTER Speed, accuracy, diligence, storage capability and versatility are some o f the key characteristics o f a com puter. A brief overview o f these characteristics are— •

Speed T h e com puter can process data very fast, at the rate o f m illions o f instructions per second. Some calculations that w ould have taken hours and days to com plete otherwise, can be com pleted in a few seconds using the com puter. For example, calculation and generation o f salary slips o f thousands o f employees o f an organization, weather forecasting th at requires analysis o f a large am o u n t o f data related to tem perature, pressure and hum idity o f various places, etc.

® Accuracy C o m p u ter provides a high degree o f accuracy. For example, the com puter can accu rately give the result o f division o f any two num bers u p to 10 decimal places. •

Diligence

0

Storage Capability

0

Versatility

W hen used for a longer period o f tim e, the com puter does n o t get tired o r fatigued. It can perform long and complex calculations with the same speed and accuracy from the start till the end.

Large volum es o f data and inform ation can be stored in the com puter and also retrieved whenever required. A lim ited am ount o f data can be stored, temporarily, in the prim ary memory. Secondary' storage devices like floppy disk and com pact disk can store a large am ount of data permanently. C o m p u ter is versatile in nature. It can perform different types o f tasks w ith the same ease. At one m om ent you can use the com puter to prepare a letter d o cu m en t and in the next m om ent you may play m usic or print a docum ent.

C om puters have several lim itations too. C o m p u ter can only perform tasks that it has been program m ed to do. C o m p u ter cannot do any work w ithout instructions from the user. It execures instructions as speci fied by the user and does noi take its own decisions. Copyrighted material

Introduction to Computer

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1.4 HISTORY OF COMPUTER U ntil the developm ent o f the first generation com puters based on vacuum tubes, there had been several developm ents in the com puting technology related to the mechanical com puting devices. T h e key devel opm ents that took place till the first com puter was developed are as follows— ®

Calculating M achines ABACUS was the first mechanical calculating device for counting o f large num bers. T he word ABACUS m eans calculating board. It consists o f bars in horizontal positions on which sets o f beads are inserted. T he horizontal bars have 10 beads each, representing units, tens, hundreds, etc. An abacus is shown in Figure 1.1

® N apiers Bones was a mechanical device built for the purpose o f m ultiplication in 1617 a d . by an English m athem atician John Napier. ®

Slide Rule was developed by an English m athem atician E dm und G u n ter in the 16th century. Using the slide rule, one could perform operations like addition, subtraction, m ultiplication and division. It was used extensively till late 1970s. Figure 1.2 shows a slide rule.

Figure 1.2

Figure 1.1

Abacus

Slide rule

® Pascal's A dding a n d Subtraction M achine was developed by Blaise Pascal. It could add and sub tract. T he m achine consisted o f wheels, gears and cylinders. ® Leibniz's M ultiplication and D ividing M achine was a mechanical device that could both m ul tiply and divide. T he G erm an philosopher and m athem atician G ottfried Leibniz built it around 1673. © Punch Card System was developed by Jac quard to control the power loom in 1801. He invented the punched card reader that could recognize the presence o f hole in the punched card as binary one and the absence o f the hole as binary zero. T he Os and Is are the basis of the m odem digital computer. A punched card is shown in Figure 1.3.

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7

are able to store m illions o f c o m p o n e n ts on a single chip. T hese co m p u ters have large m em ory req u irem en ts. T his generation o f com puters uses parallel processing that allows several instructions to be executed in parallel, instead o f serial execution. Parallel processing results in faster processing speed. T h e Intel dualcore microprocessor uses parallel processing. T h e fifth generation com puters are based on Artificial Intelligence (AI). T hey try to sim ulate the hum an way o f thinking and reasoning. Artificial Intelligence includes areas like Expert System (ES), N atural Lan guage Processing (N LP), speech recognition, voice recognition, robotics, etc.

1.6 CLASSIFICATION OF COMPUTER T h e digital com puters that are available nowadays vary in their sizes and types. T h e com puters are broadly classified into four categories (Figure 1.8) based on their size and type— (1) M icrocom puters, (2) M ini com puters, (3) M ainfram e com puters, and (4) Supercom puter.

Fast Expensive Complex Large

Slow Cheap Simple Small Figure 1.8

Classification of computers based on size and type

1.6.1 Microcomputers M icrocom puters are small, low-cost and single-user digital com puter. T hey consist o f C P U , in p u t unit, o u tp u t unit, storage unit and the software. A lthough m icrocom puters are stand-alone machines, they can be connected together to create a netw ork o f com puters that can serve m ore than one user. IBM P C based on Pentium microprocessor and Apple M acintosh are some examples o f m icrocom puters. M icrocom put ers include desktop com puters, notebook com puters or laptop, tablet com puter, handheld com puter, sm art phones and netbook, as shown in Figure 1.9.

Copyright

8____ I Basics of Computer

Tablet Figure 1.9

Laptop

Netbook

PD A

Sm art Phone

Microcomputers

® Desktop Computer or Personal Computer (PC) is the m ost com m on type o f m icrocom puter. It is a stand-alone m achine that can be placed o n the desk. Externally, it consists o f three units— key board, m onitor, and a system unit containing the C P U , memory, hard disk drive, etc. It is not very expensive and is suited to the needs o f a single user at hom e, small business units, and organizations. Apple, M icrosoft, HP, Dell and Lenovo are some o f the P C m anufacturers. ® Notebook Computers or Laptop resemble a notebook. T hey are portable and have all the features o f a desktop com puter. T he advantage o f the laptop is that it is small in size (can be p u t inside a briefcase), can be carried anywhere, has a battery backup and has all the functionality o f the desk top. Laptops can be placed on the lap while w orking (hence the name). Laptops are costlier than the desktop machines. ® Netbook These are smaller notebooks optim ized for low weight and low cost, and are designed for accessing web-based applications. Starting w ith the earliest netbook in late 2007, they have gained significant popularity now. N etbooks deliver the perform ance needed to enjoy popular activities like stream ing videos or music, emailing, Web surfing or instant messaging. T h e w ord netbook was created as a blend of Inter«
Tablet Computer has features o f the notebook com puter but it can accept input from a stylus or a pen instead o f the keyboard or mouse. It is a portable com puter. Tablet com puter are the new kind o f PCs.


Introduction to Computer 0

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H andheld Computer or Personal D igital Assistant (PDA) is a small com puter that can be held on the top o f the palm. It is small in size. Instead o f the keyboard. PD A uses a pen or a stylus for input. PDAs do not have a disk drive. T hey have a lim ited m em ory and are less powerful. PDAs can be connected to the Internet via a wireless connection. Casio and Apple are some o f the m anufacturers o f PDA. O ver the last few years, PDAs have merged into mobile phones to create sm art phones.

0

Sm art Phones are cellular phones that function both as a phone and as a small PC. T hey may use a stylus or a pen, or m ay have a small keyboard. T hey can be connected to the Internet wirelessly. T hey are used to access the electronic-m ail, dow nload music, play games, etc. Blackberry, Apple, H T C , Nokia and LG are some o f the m anufacturers o f sm art phones.

1.6.2 Minicomputers M inicom puters (Figure 1.10) are digital com puters, generally used in m ulti-user systems. T h ey have high processing speed a n d high stor age capacity than the m icrocom puters. M inicom puters can support 4—200 users simultaneously. T h e users can access the m inicom puter through their PC s or term inal. T hey are used for real-tim e applica tions in industries, research centers, etc. PD P 11. IBM (8000 series) are some o f the widely used m inicom puters. Figure 1.10

Minicomputer

1.6.3 Mainframe Computers M ainfram e com puters (Figure l . l 1) are multi-user, m ulti-program m ing and high perform ance co m p u t ers. T hey operate at a very high speed, have very large storage capacity and can handle the workload o f m any users. M ain m1 w frame com puters are large and powerful systems generally used / \1 in centralized databases. T he user accesses the m ainfram e com I puter via a term inal that may be a dum b term inal, an intelli gent term inal or a PC. A dumb terminal cannot store data or do processing o f its own. It has the in p u t and o u tp u t device only. An intelligent terminal has the input and o u tp u t device, can do processing, but, cannot store data of its own. T h e dum b and & the intelligent term inal use the processing power and the stor ja , j 1 age facility o f the m ainfram e com puter. M ainfram e com puters are used in organizations like banks or com panies, where m any people require frequent access to the same data. Some examples o f m ainfram es are C D C 6600 and IBM ES000 series.

I

1.6.4 Supercomputers S u p erco m p u ters (Figure 1.12) are the fastest a n d the m ost expensive m achines. T h e y have high processing speed co m pared to o th er co m puters. T h e speed o f a su p erco m p u ter is generally m easured in FLO PS (F L oating p o in t O p e ratio n s Per Second). Som e o f the faster su p erco m p u ters can perform trillio n s o f calculations per second. S upercom puters are b u ilt by in te rc o n n e c tin g thousands o f processors th a t can w ork in parallel.

Figure 1.11? M ainframe com puter



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Hardware consists o f the mechanical parts that make up the com puter as a m achine. T h e hardware con sists o f physical devices o f the com puter. T h e devices are required for input, o u tp u t, storage and processing o f the data. Keyboard, m onitor, hard disk drive, floppy disk drive, printer, processor and m otherboard are some o f the hardware devices.

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Parts of computer system

Software is a set o f instructions that tells the com puter about the tasks to be perform ed and how these tasks are to be perform ed. Program is a set of instructions, w ritten in a language understood by the com puter, to perform a specific task. A set o f program s and docum ents are collectively called software. The hardware o f the com puter system cannot perform any task on its own. T h e hardware needs to be instructed about the task to be perform ed. Software instructs the com puter about the task to be per form ed. T h e hardware carries o u t these tasks. Different software can be loaded on the same hardware to perform different kinds o f tasks. D ata are isolated values or raw facts, which by themselves have no m uch significance. For example, the data like 29, January, and 1994 just represent values. T h e data is provided as in p u t to the com puter, which is processed to generate some m eaningful inform ation. For example, 29, January and 1994 are processed by the com puter to give the date o f birth o f a person. Users are people who w rite com puter program s or interact w ith the com puter. T hey are also known as skinware, liveware, humanware orpeopleware. Programmers, data entry operators, system analyst and com puter hardware engineers fall into this category.

1.7.1 The Input-Process-Output Concept A com puter is an electronic device that (1) accepts data, (2) processes data, (3) generates output, and (4) stores data. T he concept o f generating output information from the input data is also referred to as input-process-output concept.

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relatives via Internet, for paying bills, for education and learning, etc. M icroprocessors are em bed ded in house hold utilities like, washing machines, TV s, food processors, hom e theatres, security devices, etc. T h e list o f applications o f com puters is so long that it is not possible to discuss all o f them here. In addition to the applications o f the com puters discussed above, com puters have also proliferated into areas like banks, investm ents, stock trading, accounting, ticket reservation, m ilitary operations, meteorological predictions, social netw orking, business organizations, police departm ent, video conferencing, telepres ence. book publishing, web newspapers, and inform ation sharing.

SUMMARY____________________________________ 0

Computer is an electronic device which accepts data as input, perform s processing on the data, and gives the desired outp u t. A com puter may be analog or digital computer.

0

tenance than the first generation co m p u t ers. T h e com putation tim e was in m icro seconds.

0

Speed, accuracy, diligence, storage capabil ity and versatility are the m ain characteristics

by the use o f IC. They consumed less power and required low maintenance compared to their predecessors. High-level languages were used for programming. T he com putation time was in nanoseconds. These computers were produced commercially.

o f computer. 0

T h e computing devices have evolved from sim ple mechanical machines, like ABACUS, N apier’s bones, Slide Rule, Pascals Adding and Subtraction M achine, Leibnizs M ulti plication and Dividing M achine, Jacquard Punched Card System, Babbages Analytical Engine and H olleriths Tabulating M achine, to the first electronic com puter.

0

Charles Babbage is called the father of com puter.

0

T h e evolution o f com puters to their present state is divided into five generations o f com puters,, based on the hardw are and software they use, their physical appearance and their com puting characteristics.

0

0

0

Fourth generation computers used m icro processors which were designed using the LSI and VLSI technology. T h e com puters became small, portable, reliable and cheap. T h e com putation time is in picoseconds. T hey became available both to the hom e user and for com m ercial use.

0

Fifth generation computers are capable o f learn ing and self organization. These com puters use SLSl chips and have large m em ory requirements. T hey use parallel processing and are based on AI. T h e fifth generation com puters are still being developed.

First generation computers were vacuum tubes based machines. These were large in size, expensive to operate and instructions were w ritten in m achine language. T h eir com putation tim e was in milliseconds.

0

Second generation computers were transis

0

to r based machines. T h ey used the stored program concept. Programs were w ritten in assembly language. T h ey were sm aller in size, less expensive and required less m ain

Third generation computers were characterized

Computers are broadly classified as m icro com puters, m inicom puters, m ainfram e com puters, and supercom puters, based on their sizes and types.

Microcomputers are small, low-cost stand alone machines. M icrocom puters include desktop com puters, notebook com puters or laptop, netbooks, tablet com puter, h an d held com puter and sm art phones.


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Basics of Computer

© Minicomputers are high processing speed m achines having m ore storage capacity than the m icrocom puters. M inicom puters can support 4-200 users simultaneously. © Mainframe computers are m ulti-user, m u lti program m ing an d high perform ance com puters. T h e y have very high speed, very large storage capacity a n d can handle large w orkloads. M ainfram e com puters are gen erally used in centralized databases. © Supercomputers are the m ost expen sive machines, having high processing speed capable o f perform ing trillions o f calculations per second. T h e speed o f a supercom puter is measured in FLOPS. Supercom puters find applications in com puting-intensive tasks. ©

Computer is an electronic device based on the input-process-output concept. In p u t/

O u tp u t U nit, C P U and M em ory unit are the three m ain components o f computer. © Input/Output Unit consists of the In p u t u n it w hich accepts data from the user and the O u tp u t u n it that provides the processed data. CPU processes the in p u t data, and, controls, coordinates and supervises the operations o f the com puter. C P U consists o f ALU, C U and Registers. T h e m em ory unit stores programs, data and o u tp u t, tem po rarily, during the processing. Additionally, storage unit o r secondary m em ory is used for the storing o f programs, data and o u t p u t permanently. © C om puters are used in various areas o f our life. Education, entertainm ent, sports, advertising, m edicine, science and engineer ing, governm ent, office and hom e are some o f the application areas o f the computers.

KEYWORDS ABACUS 3 Analog computer 2 Arithmetic Logic Unit (ALU) 13 Assembly language 5 Babbages Analytical Engine 4 Central Processing Unit (CPU) 6 Computer 2 Control Unit (CU) 13 Data 11 Desktop computer 8 Digital computer 2 Dumb terminal 9 Fifth Generation Computer 6 First Generation Computer 4 Floating point Operations Per Second (FLOPS) 9 Fourth Generation Computer 6 Hardware 4 Hollerith’s tabulator 4 Input 11

Input/Output Unit 12 Integrated Circuit (IC) 5 Intelligent terminal 9 Jacquard s punch card 3 Large Scale Integration (LSI) Leibnizs Machine 3 Machine language 4 Mainframe computers 9 Memory 13 Microcomputers 7 Microprocessor 6 Minicomputers 9 Napiers bones 3 Netbook 8 Notebook computer 8 Output 12 Parallel processing 7 Pascal’s Machine 3 Personal Computer (PC) 8 Personal Digital Assistant (PDA) 9

6

Process 12 Program 11 Punched cards 4 Second Generation Computer 5 Slide Rule 3 Smart phones 9 Software 11 Storage unit 6 Supercomputer 9 Super Large Scale Integrated (SLSI) chips 6 Tablet computer 8 Third Generation Computer 5 Transistors 5 Users 11 Vacuum Tubes 4 Very Large Scale Integration (VLSI) 6



17

QUESTIONS__________________________________ Section 1.2 1. D e fin e

a n a n a lo g c o m p u te r a n d a d ig ita l c o m p u te r .

2. Give an example each of analog computer and digi tal computer.

20. Describe the third generation computer based on the (a) Hardware (b) Software (c) Computing char acteristics (d) Physical appearance, and (c) Their applications. 21. Give two examples of third generation computers.

Section 1.3

22. List the drawbacks of the third generation computers.

3. List the main characteristics of the computer.

Section 1.5.4

4. Describe the characteristics of the computer. 5. List three significant limitations of the computer.

23. The

fourth

generation for circuitry.

computers

used

6. Explain briefly the developments in computer tech nology starting from a simple calculating machine to the first computer.

24. Describe the fourth generation computer based on the (a) Hardware (b) Software (c) Computing characteristics (d) Physical appearance and (e) Their applications.

7. What is a calculating machine?

25. Give two examples of fourth generation computers.

8. What is the key feature of the Jacquards punch card?

26. List the drawbacks of the fourth generation com puters.

9. Name the first calculating device for the counting of large numbers.

Section 1.5.5

Section 1.4

10. Who is called the Father of Computer? Section 1.5.1 11. The first generation computers used____________ for circuitry. 12. Describe the first generation computer based on the (a) Hardware (b) Software (c) Computing char acteristics (d) Physical appearance, and (e) Their applications. 13. Give two examples of first generation computers. 14. List the drawbacks of the first generation comput ers.

second

generation for circuitry.

computers

used

16 . O c M jrib c t h e .s e c o n d g e n e r a t i o n c o m p u t e r b a s e d

on the (a) Hardware (b) Software (c) Compuring characteristics (d) Physical appearance and (e) Their applications. 17. Give two examples of second generation computers. 18.

28. Describe the fifth generation computer based on the (a) Hardware (b) Software (c) Computing characteristics (d) Physical appearance and (c) Their applications. 29. Give two examples of fifth generation computers. 30. Compare in detail the five generations o f computers based on the (a) Hardware (b) Software (c) Com puting characteristics (d) Physical appearance and (e) Their applications. Also give at least one exam ple of each generation of computer.

Section 1.6.1

Section 1.5.2 15. The

27. The fifth generation computers used____________ for circuitry.

List the drawbacks of the second generation com puters.

32. Give two examples of microcomputer. 33. List three categories of microcomputers. S e c tio n

1.6.2

34. Define minicomputers. 35. Give two examples of minicomputer.

Section 1.6.3 36. Define mainframe computer. 37. Give two examples of mainframe computer.

Section 1.5.3 19. The third generation ____________ for circuitry.

31. Define microcomputer.

computers

used

38. Define a dumb terminal. 39. Define an intelligent terminal.



THE COMPUTER SYSTEM HARDWARE ■c

x: w ■i\y ./ K Y •

©

©

® © ©

Central Processing Unit (CPU) • Arithmetic logic unit • Registers • Control Unit (CU) Memory unit • Cache memory • Primary memory • Secondary memory Instruction format Instruction set Instruction cycle— Fetching, executing, storing

Why this chapter?

© ©

©

©

Microprocessor— CISC, RISC Interconnecting the units of a computer— System bus, expansion bus, external ports Performance of a computer— Registers, RAM, system clock, bus, cache memory Inside a computer cabinet— Motherboard, ports and interfaces, expansion slots, ribbon cables, memory chips, storage devices, processor

decoding,

fir

The com puter as a m achine consists of different com ponents that interact with each other to provide the desired functionality of the computer. As a user of the computer, w e need to be aw are of the m ain com ponents of the computer, their functions and the intercon & nection betw een the different com ponents of the computer. This chapter describes the different hardware com ponents of the computer.

.'•J-J & A V fr . -a.I* ? *

2.1 INTRODUCTION W h en we talk o f com puter hardware, the three related term s th at require introduction are— com puter architecture, com puter organization and com puter design. Computer architecture refers to the structure and behavior o f the com puter. It includes the specifications o f the com ponents, for example, instruction form at, instruction set and techniques for addressing memory, and how they connect to the other com po nents. Given the com ponents, computer organization focuses o n the organizational structure. It deals with how the hardware com ponents operate and the way they are connected to form the com puter. Given the system specifications, computer design focuses on the hardw are to be used and the interconnection o f parts. D ifferent kinds o f com puter, such as a P C or a m ainfram e com puter m ay have different organization; however, basic organization o f the com puter rem ains the same. A com puter consists o f three main com ponents— (1) In p u t/O u tp u t (I/O ) Unit, (2) Central Processing U nit (C PU ), and (3) M em ory Unit. T h e com puter user interacts w ith the com puter via the I/O unit. T h e purpose o f I/O unit is to provide data and instructions as in p u t to the com puter and to present relevant





The Computer System Hardware

P ro c e s s o r L lc a c h e

Figure 2.3

L 2 cach e

M N— y

23

RAM

Illustration of cache memory

0 Cache m em ory is built into the processor, and may also be located next to it on a separate chip between the C P U and RAM . Cache built into the C P U is faster than separate cache, run n in g at the speed o f the microprocessor itself. However, separate cache is roughly twice as fast as RAM.

0 T h e C P U has a built-in Level 1 (L l) cache and Level2 (L2) cache, as shown in Figure 2.3. In addition to the built-in Ll and L2 cachc, some CPU s have a separate cache chip on the m otherboard. This cache on the m otherboard is called Level 3 (L3) cache. Nowadays, high-end processor comes with built-in L3 cache, like in Intel core i7. T h e L l, L2 and L3 cache store the m ost recently run instruc tions, the next ones and the possible ones, respectively. Typically, CPU s have cache size varying from 256KB (L l), 6 M B (L2), to 12MB (L3) cache.

01C ache m em ory is very expensive, so it is smaller in size. Generally, com puters have cache m em ory o f sizes 256 KB to 2 MB.

2.3.2 Primary Memory 0 Prim ary m em ory is the m ain m em ory o f com puter. It is used to store data and instructions during the processing o f data. Prim ary m em ory is sem iconductor memory.

0 Primary m em ory is o f two kinds— Random Access M emory (RAM) and Read O nly M em ory (ROM ). 0 RAM is volatile. It stores data w hen the c o m p u te r is o n . T h e in fo rm atio n sto red in RAM gets erased w hen the c o m p u ter is tu rn e d off. RAM provides temporary storage for d ata and in stru ctio n s.

0 R O M is non-volatile memory, b u t is a read only memory. T h e storage in R O M is perm anent in nature, and is used for storing standard processing program s that perm anently reside in the co m puter. R O M comes program m ed by the m anufacturer.

0 RAM stores data and instructions during the execution o f instructions. T h e data and instructions that require processing are brought into the RAM from the storage devices like hard disk. C P U accesses the data and the instructions from RAM , as it can access it at a fast speed than the storage devices connected to the in p u t and o u tp u t unit (Figure 2.4).

0 T h e in p u t data that is entered using the in p u t unit is stored in RAM , to be m ade available d u r ing the processing o f data. Similarly, the o u tp u t data generated after processing is stored in RAM before being sent to the o u tp u t device. Any interm ediate results generated during the processing o f program are stored in RAM.

0 RAM provides a limited storage capacity, due to its high cost. Copyright



26

Basics of Computer

i k ( ) Execute

Figure 2.8

Instruction cycle

Fetch instruction from m em ory

I P lace instruction in IR

I Increm ent PC

D ecode instruction B reak into parts using instruction set architecture

E xecute instruction T h e operation im plied by instruction is perform ed

Store instruction in co m p u ter m em ory

F etch next instruction

Figure 2.9

Steps in instruction cycle

® Instructions are o f different categories. Some categories o f instructions art • M em ory access or transfer o f data between registers. • A rithm etic operations like addition and subtraction. • Logic operations such as A N D , O R and N O T. • C o n tro l the sequence, conditional connections, etc. Copyrighted

The Computer System Hardware

|

27

A C P U perform ance is measured by the num ber o f instructions it executes in a second, i.e., M IP S (m illion instructions per second), or B IP S (billion instructions per second).

2.7 MICROPROCESSOR A processors instruction set is a determ ining factor in its architecture. O n the basis o f the instruction set, m icroprocessors are classified as— Reduced Instruction Set C o m p u ter (RISC), and Com plex Instruction Set C o m p u ter (CISC). T h e x86 instruction set o f the original Intel 8086 processor is o f the C ISC type. T h e PCs are based on the x86 instruction set. ©

CISC architecture hardwires the processor with complex instructions, which are difficult to create otherwise using basic instructions. CISC combines the different instructions into one single CPU . • C IS C has a large instruction set that includes simple and fast instructions for perform ing basic tasks, as well as complex instructions that correspond to statem ents in the high level language. • An increased num ber o f instructions (200 to 300) results in a m uch more com plex processor, requiring millions o f transistors. • Instructions are o f variable lengths, using 8, 16 or 32 bits for storage. T his results in the proces sor’s tim e being spent in calculating where each instruction begins and ends. • W ith large num ber o f application software program s being w ritten for the processor, a new pro cessor has to be backwards com patible to the older version o f processors. • A M D and Cyrix are based on C ISC .

® RISC has simple, single-cycle instructions, which perform s only basic instructions. RISC archi tecture does n o t have hardw ired advanced functions. All high-level language support is done in the software. • RISC has fewer instructions and requires fewer transistors, which results in the reduced m anu facturing cost o f processor. • T h e instruction size is fixed (32 bits). T h e processor need not spend tim e in finding o u t where each instruction begins and ends. • RISC architecture has a reduced production cost com pared to C ISC processors. • T h e instructions, simple in nature, are executed in just one clock cycle, which speeds up the program execution when com pared to C IS C processors. • RISC processors can handle m ultiple instructions sim ultaneously by processing them in parallel. • Apple M ac G 3 and PowerPC are based on RISC. Processors like A thlon XP and Pentium IV use a hybrid o f both technologies. P ip e lin in g improves instruction execution speed by putting the execution steps into parallel. A C P U can receive a single instruction, begin executing it, and reccivc another instruction before it has com pleted the first. T his allows for more instructions to be perform ed, about, one instruction per clock cycle. Parallel P rocessing is the sim ultaneous execution o f instructions from the same program on differ ent processors. A program is divided into m ultiple processes that are handled in parallel in order to reduce execution time.

2.8 INTERCONNECTING THE UNITS OF A COMPUTER C P U sends data, instructions and inform ation to the com ponents inside the com puter as well as to the peripherals and devices attached to it. Bits is a set o f electronic signal pathways that allows inform ation Copyrighted






The Computer System Hardware ®

|

33

USB Ports— to connect newer peripherals like cameras, scanners and printers to the com puter. It uses a thin wire to connect to the devices, and m any devices can share that wire simultaneously.

® Firewire is another bus, used today m ostly for video cameras and external hard drives. ©

RJ45 connector (called LAN or Ethernet port) is used to connect the com puter to a netw ork. It corresponds to a netw ork card integrated into the m otherboard.

©

VGA connector for connecting a m onitor. T his connector interfaces with the built-in graphics card.

® Audio plugs (line-in, line-out and m icrophone), for connecting sound speakers and the m icro phone. T his connector interfaces w ith the built-in sound card. ®

PS/2 port to connect mouse and keyboard into PC.

© SCSI port for connecting the hard disk drives and netw ork connectors.

2.10.3 Expansion Slots T he expansion slots (Figure 2.17) are located on the motherboard. T he expansion cards are inserted in the expan sion slots. These cards give the com puter new features or increased performance. There are several types o f slots: © ISA (Industry Standard Architecture) slot— T o connect m odem and input devices. ®

PC I (Peripheral C om ponent In te rc o n n e c t) slot— To connect audio, video and graphics. T hey are m uch faster than ISA cards.

•) A G P (Accelerated G raphic Port) slot— A fast port for a graphics card. ©

PCI (Peripheral Component Interconnect) Express slot— Faster bus architecture than AGP and PCI buses.

©

PC Card— It is used in laptop computers. It includes Wi-Fi card, network card and external modem.

Figure 2.17

Expansion slots

2.10.4 Ribbon Cables Ribbon cables (Figure 2.18) are flat, insulated and consist o f several tiny wires m oulded together that carry data to different com ponents on the m otherboard. T here is a wire for each bit o f the word or byte and additional wires to coordinate the activity o f moving inform ation. T hey also connect the floppy drives, disk drives and C D -R O M drives to the connectors in the m otherboard. Nowadays, Serial Advanced Technol ogy A ttachm ent (SATA) cables have replaced the ribbon cables to connect the drives to the m otherboard.








Computer M em ory H igh

H igh

|

41

Low

Figure 3.2

Memory hierarchy

T h e internal m em ory and external m em ory are the two broad categories o f m em ory used in the com puter. T h e internal m em ory consists o f the C P U registers, cache m em ory and prim ary m emory. T h e internal m em ory is used by the C P U to perform the com puting tasks. T h e external m em ory is also called the secondary m emory. T h e secondary m em ory is used to store the large am o u n t of data and the software.

In general, referring to the com puter m em ory usually means the internal memory. V _____ __ -.......................................................................................................................................................... . - V 0

Internal Memory— T h e key features o f internal m em ory are— (1) lim ited storage capacity, (2) tem porary storage, (3) fast access, and (4) high cost. Registers, cache memory, and primary' m em ory constitute the internal memory. T h e prim ary m em ory is further o f two kinds— RAM and R O M . Registers are the fastest and the m ost expensive am ong all the m em ory types. T h e registers are located inside the C P U , and are directly accessible by the C P U . T h e speed o f registers is between 1—2 ns (nanosecond). T h e sum o f the size o f registers is about 200B. Cachc m em ory is next in the hierarchy and is placed between the C P U and the main memory. T h e speed ol cache is between 2 -1 0 ns. The cache size varies between 32 KB to 4M B. Any program or data that has to be executed m ust be brought into RAM from the secondary memory. Prim ary m em ory is relatively slower than the cache memory. T he speed o f RAM is around 60ns. T h e RAM size varies from 512KB to 3GB.

0

Secondary M emory — T he key features o f secondary m em ory storage devices are— (1) very high storage capacity, (2) perm anent storage (non-volatile), unless erased by user, (3) relatively slower access, (4) stores data and instructions that are not currently being used by C P U b u t may be required later for processing, and (5) cheapest am ong all memory. T h e storage devices consist o f two parts— drive and device. For example, m agnetic rape drive and m agnetic tape, m agnetic disk drive and disk, and, optical disk drive and disk. T h e speed o f m agnetic disk is around 60m s. C o p y rig h te d m aterial




Computer M em ory

|

45

® T h e R O M m em ory chip (Figure 3.5) stores the Basic Input Output System (BIOS). BIOS provides the processor with the inform ation required to boot the system. It provides the system with the settings and resources that are available on the system. BIOS is a perm anent p art o f the com puter. It does n o t load from disk but instead is stored in a RO M m em ory chip. T h e program code in the BIOS differs from ordinary software since it acts as an integral part o f the com puter. W hen the com puter is turned on, the BIOS does the following things—

CM OS

battery

ROM BIO S

Figure 3.5

ROM BIOS and CMOS battery on a motherboard

• Power On Self Test (POST) is a program that runs autom atically when the system is booted. BIOS perform s the power-on self-test. It checks that the m ajor hardware com ponents are w orking properly. • BIOS setup program , which is a built-in utility in BIOS, lets the user set the m any functions that control how the com puter works. BIOS displays the system settings and finds the bootable devices. It loads the interrupt handlers and device drivers. It also initializes the registers. • Bootstrap Loader is a program whose purpose is to start the com puter software for operation when the power is turned on. It loads the operating system into RAM and launches it. It generally seeks the operating system on the hard disk. T he bootstrap loader resides in the R O M . T h e BIOS initi ates the bootstrap sequence. ®

R O M s are o f different kinds. T hey have evolved from the fixed read only m em ory to the ones that can be program m ed and re-program m ed. T hey vary in the num ber o f re-writes and the m ethod used for the re-writing. Program m able R O M (PR O M ), Erasable Program m able R O M (EPR O M ) and Electrically Erasable Program m able R O M (EEPR O M ) are some o f the RO M s. All the differ en t kinds o f R O M retain their content w hen the power is turned off.

• PROM can be program m ed w ith a special tool, b u t after it has been program m ed the contents cannot be changed. PR O M m em ories have thousands o f fuses (or diodes). H igh voltage (12 V) is applied to the fuses to be burnt. T h e b u rn t fuses correspond to 0 and the others to 1. • EPRO M can be program m ed in a sim ilar way as PR O M , b u t it can be erased by exposing it to ultra violet light and re-program m ed. E PR O M chips have to be removed from the com puter for re-writing.




Computer M em ory

|

An. 49

Track sector

sector

Figure 3.10

Tracks and sectors of a disk

0

M agnetic disk is inserted into a m agnetic disk drive for access. T h e drive consists o f a read/write head that is attached to a disk arm, which moves the head. T h e disk arm can move inward and outw ard on the disk.

0

D uring reading or w riting to disk, the m otor o f disk drive moves the disk at high speed (6 0 -1 5 0 times/sec.)

0

Accessing data o n the disk requires the following— • T h e read/w rite head is positioned to the desired track where the data is to be read from or w rit ten to. T h e tim e taken to move the read/write head to the desired track is called the seek time. • O nce the read/w rite head is at the right track, then the head waits for right sector to com e under it (disk is m oving at high speed). T h e tim e taken for desired sector o f the track to com e under read/w rite head is called the latency time. • O nce the read/w rite head is positioned at the right track and sector, the data has to be w ritten to disk or read from disk. T h e rate at w hich data is w ritten to disk or read from disk is called data

transfer rate. • T h e sum o f seek tim e, latency tim e and tim e for data transfer is the access tim e o f the disk. 0

T h e storage capacity o f disk drive is m easured in gigabytes (GB).

©

Large disk storage is created by stacking together m ultiple disks. A set o f same tracks o n all disks form s a cylinder. Each disk has its ow n read/w rite head which w ork in coordination.

© A disk can also have tracks and sectors on both sides. Such a disk is called double-sided disk. T h e features o f m agnetic disk are— © C heap storage device © C an store a large am ount o f data © Easy to carry or transport © Suitable for frequently read/w rite data © Fast access device © M ore reliable storage device © To be prevented from dust, as the read/w rite head flies over the disk. Any dust particle in between can corrupt the disk.

______ 50

|

Basics of Computer

Finding data on a m agnetic disk is as follows— © In order to use a disk, it has to be form atted. Form atting includes assigning addresses to various locations on disk, assigning location o f root directory and checking for defects on the surface o f disk. © D uring form atting, the tracks and sectors o f a disk are labeled, which provides an address to each location o f the disk. © T here are different m ethods to form at a disk. File Allocation Table (FAT) is the com m only used logical form at for disk form atting perform ed by W indows. © Four areas are created when a disk is form atted using FAT—

• Boot Sector

It contains the program that runs when the com puter is started. T h e program checks if the disk has files required to run the operating system. It then transfers control to an operating system program which continues the startup process. Boot sector also contains infor m ation about the disk, like num ber o f bytes per sector and n u m ber o f sectors per track. This inform ation is required by the operating system to access the data on the disk. • File Allocation Table It records the location o f each file and status o f each sector. W hile read ing or w riting to disk, operating system checks the FAT to find free area o r locate where data is stored on disk, respectively. • Root Directory T his is the m ain folder o f disk. It contains other folders in it, creating a hier archical system o f folders. T h e root directory contains inform ation about all folders on the disk. • D ata Area T h e rem aining area o f the disk (after boot sector, FAT, root directory) is the data area. It stores the program files and data files that are stored on the disk. © T he W indow s XP and the W indow s 2000 operating system use the N ew Technology File System (N TFS) 5 file system. T h e N T F S 5 file system offers better security and increased perform ance. It allows using o f filenames that are more than eight characters long. ©

Floppy disk, hard disk and zip disk are the different types o f m agnetic disks.

3.10.1 Floppy Disk © Floppy disk (FD) is a flat, round, single disk m ade o f M ylar plastic and enclosed in square plastic jacket (Figure 3.11). © Floppy Disk Drive (F D D ) is the disk drive for floppy disk. © T h e floppy disk is inserted into the floppy disk drive to read or w rite data to it. © Floppy disk has a w rite-protcct slide tab that prevents a user from w riting to it. © A floppy disk may be single-sided or double-sided disk, i.e., data can be read and w ritten on one and both sides o f floppy disk, respectively. © T hey are portable. T hey can be removed from the disk drive, carried o r stored separately. © T h e y are small and inexpensive. © F lo p p y disks are slower to access than hard disk. They have less storage capacity and are less expensive than hard disk. Figure 3 .11

Floppy disk

© T h e y com e in two basic sizes— 5 -lA inch and 3 -Vi inch. C o p y rig h te d m aterial

Computer M em ory

|

51

® T h e 5 -V\ inch disk came around 1987. It can store 360 KB to 1.2 M B o f data. ® T h e 3-Vz inch disk has capacity o f 400 KB to 1.44 M B. It usually contains 40 tracks a n d 18 sectors per track and can store 512 bytes per sector.

3.10.2 Hard Disk ® A hard disk (H D ) consists o f one or m ore platters divided into concentric tracks a n d sectors. It is m o u n ted on a central spindle, like a stack. It can be read by a read/w rite head that pivots across the rotating disks. T h e data is stored on the platters covered w ith m agnetic coating (Figure 3.12).

Spindle

arms

head

Figure 3.12

Parts of hard disk

® H a rd disk is a fixed disk. T he disk is n o t removable from the drive, unlike floppy disk. ® T h e hard disk and H ard D isk Drive (H D D ) is a single unit. ® H ard disk can store m uch m ore data than floppy disk. T h e data in hard disk are packed m ore closely (because fast spinning uses smaller m agnetic charges) and they have m ultiple platters, w ith data being stored on b oth sides o f each platter. Large capacity hard disks m ay have 12 o r m ore platters. ®

U nlike floppy disk, the read/w rite head o f hard disk does n o t touch the disk d u rin g accessing.

® H ard disk can spin at the speed o f up to 10,000 revolutions per m inute a n d have an access tim e o f 9 -1 4 ms. It stores 512 bytes per sector b u t the num ber o f sectors are m ore per track (54 o r more) than floppy disk. S

Nowadays, hard disks are available that can store up to 500 G B o f data. Generally, PCs come with 160 GB hard disk.

®

H ard disk is the key secondary storage device o f com puter. T h e operating system is stored o n the hard disk. T he perform ance o f com puter like speed o f com puter boot up, loading o f program s to

C o p y rig h te d m aterial

________ 52

| Basics o f Computer prim ary m emory, loading o f large files like images, video, audio etc., is also dependent on the hard disk. 0

Nowadays, portable external hard disk drive is available which can be attached to the USB drive o f the com puter. T hey com e in the storage capacities o f 80 GB to 500 GB.

3.10.3 Zip Disk 0 T hey are high-capacity removable disk and drive. 0 T hey have the speed and capacity o f hard disk and portability o f

floppy disk. 0 Z ip disk are o f the same size as floppy disk, i.e., 3 -Vi inch b u t

have a m uch higher capacity than the floppy disk (Figure 3.13). 0 Z ip disk and drive were m ade by Iomega C orp. It comes as a

com plete unit— disk, drive, connection cable, power cord and operating system. It can be connected to the com puter system externally using a parallel chord o r SCSI cable. 3.13

Zip disk

0 T h eir capacity ranges from 100 M B to 750 M B. T hey can be

used to store large files, audio and video data.

3.11 OPTICAL DISK O ptical disk (Figure 3.14) is a flat and circular disk which is coated w ith reflective plastic m aterial that can be altered by laser light. O ptical disk does n o t use m agnetism . T h e bits 1 and 0 are stored as spots that are relatively bright and light, respectively. 0

An optical disk consists o f a single spiral track that starts from the edge to the centre o f disk. D ue to its spiral shape, it can access large am o u n t o f data sequentially, for example m usic and video. T he random access on optical disk is slower than that o f m agnetic disk, due to its spiral shape.

0

T h e tracks o n optical disk are further divided into sectors w hich are o f same length. T hus, the sectors near the centre o f disk w rap around the disk longer th an the sectors on the edges o f disk. Reading the disk thus requires spinning the disk foster w hen reading near the centre and slower w hen reading near the edge o f disk. O ptical disks are generally slower th an hard disks. Figure 3.15 shows the tracks and sectors in a m agnetic disk and optical disk.


Computer Memory

Track (concentric circles) Sector wider at edge than center Magnetic disk

Spiral track

1____ 5 3

Sectors of same width Optical disk

figure 3>15 Sectors and track in magnetic disk and optical disk ® O ptical disks can store large am o u n t o f data, up to 6 G B , in a small space. C om m only used optical disks store 6 0 0 -7 0 0 M B o f data. ® T h e access tim e for an optical disk ranges from 100 to 200 ms. ® T here are tw o m ost com m on categories o f optical disks— read-only optical disks and recordable optical disks.

3.11.1 CD-ROM ® Originally, C om pact D isk (C D ) was a popular m edium for storing music. Now, it is used in com puters to store data and is called C om pact Disk-Read O n ly M em ory (C D -R O M ). ® As the nam e suggests, C D -R O M (Figure 3.16) is an optical disk th at can only be read and n o t w ritten on. C D -R O M is w ritten on by the m anufacturer o f the C D -R O M using the laser light. ® A C D -R O M drive reads data from the com pact disk. D ata is stored as pits (depressions) and lands (flat area) on C D -R O M disk. W hen the laser light is focused on the disk, the pits scatter the light (interpreted as 0) and the lands reflect the light to a sensor (interpreted as 1). ® As C D -R O M is read only, n o changes can be m ade into the data contained in it. ® Since there is n o head touching the disk, b u t a laser light, C D -R O M does n o t get w orn o u t easily. ® T h e storage density o f C D -R O M is very high and cost is low as compared to floppy disk and hard disk. ® Access tim e o f C D -R O M is less. C D -R O M drives can read data at 150Kbps. T h ey com e in m ul tiples o f this speed like— 2x, 4x, 52x, 75x, etc. ® It is a com m only used m edium for distributing software a n d large data.

3.11.2 DVD-ROM ® D igital Video Disk-Read O n ly M em ory (D V D -R O M ) is an optical storage device used to store digital video or com puter data (Figure 3.17). ®

D V D s look like C D s, in shape a n d physical size.





I

Com■ p u te r M e m o ry user, have slow access, store the data and instruc tions that are not currently being used by C PU , and are cheapest among all memory. M agnetic disk and optical disk are storage devices.

®

Organization o f memory with respect to the C PU , is as follows— registers are placed inside C PU , cache memory is placed inside C PU , prim ary m em ory is placed next in the hierarchy, and secondary memory is the farthest from CPU .

0

Registers are very high-speed storage areas located inside the C PU . Registers are manipulated direcdy by the control unit o f the C PU during instruction execution.

0

Cache, the fast memory, is placed between the C P U and the RAM. T he contents from the RAM are stored in the cache.

0

RAM stores data and instructions during the operation o f com puter. RAM is a random access volatile m em ory having lim ited size due to its high cost. RAM affects the speed and pow er o f th e com puter.

1

© Magnetic tapes are inexpensive, can store a large amount of data, are easy to transport, are slow access device, and are suitable for back-up storage. © Magnetic disks are cheap storage device, can store a large amount of data, are easy to carry, are suitable for frequently read/write data and are fast access device. Access time o f disk is the sum o f seek time, latency time and time for data transfer. ® Floppy disk is a flat, round, single disk enclosed in a jacket. It is portable, small, inexpensive and slower to access than hard disk. It comes in two basic sizes— 5-V4 inch and 3-V4 inch. ® Hard disk is a fixed disk and can store much more data than floppy disk. Hard disk is the key secondary storage device of computer. © Zip disk have the speed and capacity of hard disk and portability of floppy disk. ©

Optical disk consists of a single spiral track that starts from the edge to the centre o f disk. It can store large amount of data in small space.

©

CD-ROM is an optical disk that can only be read and not written on. It has high-storage density and is a low-cost device compared to floppy disk and hard disk.

® ROM is a non-volatile prim ary m em ory which stores

0

_

digital camera, mobile phone, printer, laptop com puter, and MP3 players.

© RAM memory chips are o f two types— D RAM and SRAM. DRAM is used as main m em ory as it is small and cheap. SRAM chip is used in cache m em ory due to its high speed.

—

57

the data needed for the start up o f the computer. Instructions to initialize different devices attached to com puter and the bootstrap loader are stored in R O M . PRO M , EPRO M and EEPRO M are some o f the ROM s.

© DVD-ROM is a high-density optical storage device which stores data on both sides o f the disk. It is used to store a full-length movie.

Flash memory is a kind o f semiconductor-based non

©

volatile, rewritable com puter memory. It is used in

0

Recordable optical disks are CD-R, CD-RW and DVD-R.

Computer uses its memory from the time you switch on the computer till you switch it off.

KEYWORDS Access time 40 Basic Input Output System (BIOS) 45 Bit 40 Boot sector 50 Bootstrap loader 45 Byte 40 Cache Hit 42 Cache memory 42

Compact Disk - Read Only Memory (CD-ROM) 53 Compact Disk-Recordable (CD-R) 55 Compact Disk-ReWritable (CD-RW) 55 Complementary Metal-Oxide Semiconductor (CMOS) 45 Data Transfer Rate 49

(DVD-R) 55 Direct Access 46 Dual Inline Memory Module (DIMM) 44 Dynamic RAM (DRAM) 43 Electrically Erasable Programmable ROM (EEPROM) 45 Erasable Programmable ROM

Cache Miss 42 Compact Disk (CD)

Digital Video Disk-Read Only Memory (DVD-ROM) 53

(EPROM) 45 File Allocation Table (FAT)

53

Digital Video Disk-Recordable

50





INPUT A N D DUTPUT DEVICES 0 0 0

0

& * * • .£ '

5.

*:•:•?>'?!

ihvrf '4 A:
Input-output unit— Input unit, output unit Input devices— Human data entry devices, source data entry devices * Human data entry devices • Keyboard • Pointing devices— Mouse, trackball, joystick, digitizing tablet • Pick devices— Light pen, touch screen Source data entry devices • Audio input device (microphone, sound card, speech recognition) • Video input device (video camera, digital camera) • Optical input devices— Scanner (hand held, flat bed), OCR, MICR, OMR, barcode reader

0 0

0

0 ®

Output devices— Hard copy devices, soft copy devices Hard copy devices ♦ Printer— Impact printers (dot matrix, daisywheel, drum), non-impact printers (ink-jet, laser) ♦ Plotter— Drum plotter, flatbed plotter ♦ Computer output on microfilm (microfiche) Soft copy devices— Monitor, visual display terminal, video output, audio response (speakers, headphone) I/O port— Parallel port, serial port, USB port, firewire port Working of I/O system— I/O devices, device controller, device driver

rS .sjL -

W h a t is the use of the com puter for us? W e m ay w ant to process data, w rite project reI ports, listen to sound recordings, watch a m ovie and do m any m ore things. But to do any :: of these things, w e should be able to p ro vid e the data to the com puter and also get the outp ut from it. The in p ut devices and output devices are used this purpose. The aim of this t chapter is to introduce the different kinds of in p ut and output devices.

I

l .-?j:

‘i « i - '••<:£’

.vs%'. c V -

4.1 INTRODUCTION A com puter interacts w ith the external environm ent via the in p u t-o u tp u t (I/O ) devices attached to it. In p u t device is used for providing data and instructions to the com puter. After processing the in p u t data, com puter provides o u tp u t to the user via the o u tp u t device. T h e I/O devices that arc attached, externally, to the com puter m achine are also called peripheral devices. D ifferent kinds o f in p u t and o u tp u t devices are used for different kinds o f in p u t and o u tp u t requirem ents. In this chapter, we shall discuss different kinds o f in p u t devices and o u tp u t devices.

C o p y rig h te d m a te ria l'




Input and O utp ut Devices

|

65

4.4.2 Pointing Devices Pointing devices are used for providing the input to com puter by m oving the device to p o in t to a location on com puter m onitor. T h e input data is not typed; instead, the data is entered by m oving the pointing device. T h e cursor on the com puter m onitor moves with the m oving pointing device. O perations like move, click and drag can be perform ed using the pointing devices. M ouse, trackball, joystick and digitiz ing tablet are som e o f the com m on pointing devices.

4.4.2.7 Mouse Features

It is the m ost com m on p o in tin g in p u t device. T h e data is entered by p o in tin g the m ouse to a location on the com puter screen. T h e m ouse m ay also be used to position the cursor on screen, m ove an object by dragging, or select an object by clicking. T h e key benefit o f using a m ouse is th at the cursor moves w ith the m ouse. So, the cursor can be positioned at any location on the screen by sim ply m oving the m ouse. M oreover, it provides an easy way to select and choose com m ands from m enus, dialog boxes, icons, etc. M ouse is used extensively, w hile w orking w ith graphics elem ents such as line, curve, shapes, etc. Description M ouse is a small hand-held device having two or three buttons on its u pper side. In addi tion to the buttons, m ouse also has a small wheel between the buttons. Figure 4.3 (i) shows a mouse. T h e wheel o f the m ouse is used for the up and dow n m ovem ent, for example, scrolling a long docum ent. A m ouse is classified as physical mouse or optical mouse.

Figure 4.3

Physical M ouse

(i) Mouse, (ii) A user working with a mouse

has a rubber ball on the bottom side th at protrudes w hen the m ouse is moved. It requires a sm ooth, dust free surface, such as a m ouse pad, on which it is rolled. O ptical Mouse uses a Light E m itting D iode (LED) and a sensor to detect the m ovem ent o f mouse. O ptical mouse requires an opaque flat surface underneath it. O ptical mouse was introduced by M icrosoft in 1999. O ptical m ouse is better than physical m ouse as there is no moving part that can cause wear and tear, and d irt cannot get inside it. A user is w orking w ith an optical m ouse in Figure 4.3 (ii). W orking In a plrysical mouse, rollers and sensors are used to sense the direction and rate o f m ovem ent o f m ouse. W h en the ball o f m ouse moves, the rollers sense th e horizontal and vertical m ovem ent and





69

generally used in applications like A utom ated Teller M achine (ATM ), public inform ation com puters like hospitals, airline reservation, railway reservation, superm arkets, etc. (Figure 4.8). Description Touch scrccn consists o f a clear glass panel that is placed over the view area o f com puter screen. In addition to the glass panel with sensors, it has a device driver, and a controller that translates the inform ation captured by the glass panel sensors to a form that the com puter can understand. W orking Touch screens have an infrared beam that criss-cross the surface o f screen. W hen a fingertip is touched on the screen, the beam is broken, and the location is recorded. Some touch screens have ultra sonic acoustic waves that cross the surface o f screen. W hen a fingertip is touched on the screen, the wave is interrupted, and the location is recorded. T h e recorded location is sent to the com puter via the controller o f touch screen, in a form that the com puter can understand.

4.5 SOURCE DATA ENTRY DEVICES Source data entry devices are used for audio input, video input and to enter the source docum ent directly to the com puter. Source data entry devices do not require data to be typed-in, keyed-in o r pointed to a particular location.

4.5.1 Audio Input Device A udio input can be provided to the com puter using hum an voice or speech. Audio in p u t to the com puter can be used for different purposes. It can be used for m aking telephone calls, for audio and video confer encing over Internet, to record voice, to create audio files and em bed these files to be sent over e-mail, or, to translate spoken words into text, etc. A udio in p u t devices like a microphone is used to input a person’s voice into the com puter. A sound card (Figure 4.9 (i)) translates analog audio signals from m icrophone into digital codes that the com puter can store and process. Sound card also translates back the digital sound into analog signals that can be sent to the speakers. Translating spoken words into text is also known as speech recognition or voice recognition. T h e audio in p u t along with the software for voice recognition forms the speech recognition system or voice recognition system. Software for T h e c o m p u te r can be operated using voice co m S ound card recording an d editing m ands. T h e user can dictate the com m ands to the sound com p u ter, instead o f typing them . T h e co m p u ter has to be trained to recognize the voice o f user Figure 4.9 (i) Sound card, (ii) Audacity software using the speech patterns and p ro n u n ciatio n o f w o rd s. T h e s y s te m th u s a d a p ts to th e v o ic c o f user.

Speech recognition system s are costly and difficult to develop. T hey are generally used by people w ho have difficulty in typing, people w ith disabilities or by corporate w orld for d ictatio n . A udio in p u t can be recorded on an m p3 recorder and provided as an in p u t to com puter. O p en source softw are like A udacity is used for recording and ed itin g of audio files (Figure 4 .9 (ii)).

4.5.2 Video Input Device Video in p u t is provided to the com puter using video camera and digital camera (Figure 4.10). Video cam era can capture full m otion video images. T h e images are digitized and can be compressed and stored in the com puter disk. W ebcam is a com m on video camera device. It is placed on the com puter above the screen to capture the images o f the user w ho is w orking on the com puter. A video capture card allows the user to connect video devices like cam corders to the com puter.







|

75

(sharpness and clarity o f print) o f the printer is determ ined by the resolution o f the printer. Resolution is m easured in dots per inch (dpi). Printers with a high resolution (more dpi) provide better quality output. D ifferent kinds o f printers are available for different types o f applications. Printers are classified into two categories— im pact printer and non-im pact printer. Impact printers use the typew riter approach o f physically striking a typeface against the paper and inked ribbon. Im pact printers can prin t a character or an entire line at a time. Im pact printers are low-cost p rin t ers useful for bulk printing. D o t m atrix printers, daisy wheel printers and d ru m printers are examples o f im pact printers.

® D ot M atrix Printers (Figure 4.17) p rin t one character at a tim e. T h e speed o f d o t m atrix p rin ter lies between 200 and 600 characters per second (cps) and their resolution ranges from 72 to 360 dpi. D ot m atrix printers nor mally com e in two sizes— 80 colum n printer and 132 colum n printer. D o t m atrix p rin t ers can p rin t alphanum eric characters, special characters, charts and graphs. T hey can prin t only in black and w hite. Some d o t m atrix printers can p rin t in both directions - left to right and right to left. D o t m atrix printers are com m only used for p rin tin g in applications like payroll and accounting.

© Daisy W heel Printers (Figure 4.18) print one character at a time. T hey produce letter qual ity d o cu m ent which is better than a docum ent p rin ted by a d o t m atrix printer. T h e speed o f daisy wheel printers is about 100 cps. T he p rin t head o f the printer is like a daisy flower, hence the name. These printers are slow, can only p rin t text (not graphics), and arc costly in com parison to dot matrix printers. Daisy wheel printers are used where high quality prin tin g is needed and no graphics is needed.

Figure 4.18

Daisy wheel for printers

© D rum Printers are line printers. T hey are expensive and faster than character printers b u t produce a low quality output. T hey can print 2 0 0 -2 5 0 0 lines per m inute. D rum printers arc generally used for volum inous p rin t outputs.

Non-Impact Printers do n o t hit o r im pact a ribbon to print. T hey use electro-static chemicals and ink-jet technologies. N on-im pact printers are faster and quieter than im pact printers. T hey produce high quality o u tp u t and can be used for printin g text and graphics both in black and w hite, and color. Ink-jet printers and laser printers are non-im pact printers.

© Ink-jet Printers spray ink drops directly on the paper like a jet (Figure 4.19 (i)). T h eir resolution is m ore than 500 dpi. T hey produce high quality graphics and text. Ink-jet printers are com m only found in hom es and offices.

© Laser Printers (Figure 4.19 (ii)) provide highest quality o f text and graphics printing. I-aser printers process and store the entire page before printing and are also know n as page printers. T h e laser printer can prin t 5-24 pages o f text per m inute and their resolution ranges from 400 to





Figure 4.23

Figure 4.24

79

LC D m o n ito r

A user viewing the output on a LCD monitor C o p y rig h te d m aterial






Input and O utp ut Devices 35. Name three optical scanncr devices.

62. Describe the three factors on which the clarity o f image on the com puter scrccn depends.

36. Why is a scanncr used? 37. Describe scanners.

hand-held

85

scanners

and

flat-bed

63. Name the three factors on which the clarity o f image on the com puter screen depends.

64. Name some color adapters.

38. What is the purpose of OCR software in optical character recognition?

65. W hat is a visual display terminal?

39. An application where MICR is commonly used is

66. W hy arc screen image projectors used? 6 7 . Describe how the audio response system works.

40. Name an application of OMR.

68. Name two applications o f audio response system.

41. How docs optical character reader recognize char acters?

Section 4.7-4.8

42. How docs magnetic ink charactcr reader recognize the magnetic characters? 43. How docs optical mark reader recognize marks? 44. What is the use of barcode reader?

6 9 . Name the different types o f I/O ports. 7 0 . Nam e at least one device each that can be con nected to the serial port, parallel port, USB port, M ID I port and firewire.

7 1. Explain the working o f the I/O system. 72. W hat is the purpose o f ports, buses and controllers

Section 4.6-4.6.1.1 45. Dot Matrix printers come in two sizes— _ column printer a n d ______ column printer.

in the I/O system?

73. W hat is a devicc driver? 74. W hat is the use o f the device driver?

46. The sharpness and clarity of print of the printer is determined by th e _______ of printer.

75. Is device controller a hardware or software?

47. Resolution of printer is measured i n _______ .

76. Is device driver a hardware or software?

48. Describe a dot-matrix printer. 49. Describe a daisywheel printer.

Extra Questions

50. Dot matrix and daisy wheel printers are charactcr printer but drum printer is a _______ printer and laser printer is a _______ printer.

77 . Give full form o f the following abbreviations

51. Describe non-impact printers.

Section 4.6.1.2—4.6.2.4 52. What is the use of a plotter? 53. Plotters are of two kinds—____

(i) I/O

(ii) LED

(iii) CAD

(iv) ATxM

(v) M IC R

(vi) O M R

(vii) O C R

(viii) dpi

(ix) cps

(x) CAM

(xi) C O M

(xii) C R T

(xiii) LCD

(xiv) V D T

(xv) USB

(xvi) M ID I

.plotter and

___________p lo tte r .

78. Write short notes on (a) Input-iutput unit

(b) Input Unit

(c) O u tp u t unit

(d) Keyboard

(e) Mouse

(f) Trackball

(g) Joystick

(h) Digitizing tablet

57. Give a description of the monitor.

(i) Light pen

(j) Touch screen

58. Define the resolution of the screen.

(k) Input devices

(I) Audio input dcvice

59. Define the refresh rate of the scrccn.

(m) Video input device (n) Optical input deviccs

60. Define the dot pitch of the screcn.

(o) Scanner

(p) M IC R

61. The common resolution of computer screen is a n d ________.

(q) OxMR

(r) O C R

(s) Printer

(t) Impact printers

54. Name two applications where plotters are used. 55. Define a microfilm. 56. When do we use a microfilm?





Data Representation 0

|

89____

T h e position value and quantity o f a digit at different positions in a n u m ber are as follow* Position: Position Value: Q uantity:

3 103 1000

2 102 100

1 10' 10

0 10° 1

-2 10-2 1/100

-1 10-* 1/10

-3 10-3 1/1000

5.2.2 Binary Number System 0

T h e binary num ber system consists o f two digits— 0 and 1.

0

All binary num bers are form ed using com bination o f 0 and 1. For example, 1001, 11000011 and 10110101 .

0

T h e position value and quantity o f a digit at different positions in a n u m b er are as follows— Position: Position Value: Q uantity:

3 23 8

2 22 4

1

V 2

0 2° 1

.

-1 2 '1 1/2

-2 2"2 1/4

-3 2“3 1/8

5.2.3 O ctal Number System 0

T h e octal num ber system consists o f eight digits— 0 to 1.

0

All octal num bers are represented using these eight digits. For example, 273, 103, 2375, etc.

0

T h e position value and quantity o f a digit at different positions in a n u m ber are as follows— Position: Position Value: Q uantity:

3 83 512

2 82 64

1 8' 8

0 8° 1

-2 8~2 1/64

-1 8-' 1/8

-3 8-3 1/512

5.2.4 Hexadecimal Number System 0

T h e hexadecimal num ber system consists o f sixteen digits— 0 to 9, A, B, C , D , E, F, where (A is for 10, B is for 11, 0 1 2 , D -13, E-14, F-15).

0

All hexadecim al num bers are represented using these 16 digits. For example, 3FA, 87B, 113, etc.

0

T h e position value and quantity o f a digit at different positions in a n u m b er are as follows— Position: Position Value: Q uantity:

3 163 4096

2 162 256

1 16 1 16

0 16° 1

.

- 1 16~‘ 1/16

-

2 - 3 16"2 16"3 1/256 1/4096

Table 5.1 summ arizes the base, digits and largest digit for the above discussed n u m ber systems. Table 5.2 shows the binary, octal a n d hexadecimal equivalents o f the decim al num bers 0 -1 6 . Base

Digits

Decim al

10

0 -9

9

Binary

2

0,1

1

O ctal

8

0 -7

7

Hexadecim al

16

0 -9 , A, B, C, D, E, F

F (15)

Table 5.1

Largest D igit

Summary of number system C o p y rig h te d m aterial




Data Representation (3)

Record the non-fractionaJ part o f the resulting num ber.

(4)

Repeat the above steps at least four times.

(5) W rite the digits in the non-fractional part starting from upwards to downwards.

C onvert 0.2345 from Base 10 to Base 2. 0.2345 x2 0.4690 .4690 ___x_2 0.9380 .9380 ____ * 2

1.8760 .8760 1.7520 .7520 ___ x_2

1.5040 .5040 ___ x .2

1.0080 T h e binary equivalent o f (0.2345),0 is (0.001 111),

Example 5a:

C onvert 0.865 from Base 10 to Base 2, 8 a n d 16

0.865

0.865

__*2

__JLS

1.730

6.920 _JL 8 7.360

_& 2 1.460 x2 0.920

___ X..8 2.880

____ x l

1.840 . x.2 1.680 ___x_2 1.360 The binary equivalent of (.865)l0 is (.110111)2

7.040 The octal equivalent of (0.865)10 is (.6727)8

0.865 _x_j_6 5190 865 x 13.840 x 16 5040 _§40x_ 13.440 x 16 2640 -44.0 .x 7.040 The num ber 13 in hexadeci mal is D. The hexadecim al equivalent of (O.865)10 is (.DD7),'16





























































































































































































































































You have either reached a p a ge that is unavailable for view ing or reached your view ing lim it for this book.





























































Computer Fundamentals A n ita G oel Any undergraduate course, irrespective of the streams— commerce, humanities, management, science or engineering— cannot be completed without a basic understanding of computers. This book has been written keeping in mind the requirements of this vast audience. The language used in the book is lucid, simple and reader-friendly so that a novice can easily comprehend underlying concepts in computing. Logical organization of the chapters, step-by-step presentation of the concepts, illustrations, flow charts, photographs (both color and black-and-white) and chapter-end exercises makes the book a perfect choice for an introductory course.

9

CONTEMPORARY IN COVERAGE

EXCLUSIVE AND EXHAUSTIVE CHAPTERS

I

Windows Vista and Windows 7

I

Information Systems

I

Flash, SIMM and DIMM Memory

I

Fundamentals of Databases

I • Wireless Networking

I

Computer Security

I

I

MS Access and LaTeX

I

Network and Internet Connections

Notebook, Netbook and Smartphones

I Aspect Oriented Programming (AOP) I

Digital Signature and Biometrics

PRACTICE WHILE YOU LEARN

SUPPLEMENTS FOR SUPPORT

I

I Assembling a PC

I I

Lecture Slides Solution Manual

I Working with MS Office 2007

I

mQuest

Creating MP3 Files from an Audio CD

Anita Goel is Associate Professor, Department of Computer Science, Dyal Singh College, University of Delhi. She has teaching experience of over two decades. She is guiding several students for their doctoral studies, and has several national and international research publications to her credit. She has been appointed as Fellow for Computer Science, Institute of Life Long Learning (ILLL), at the University of Delhi.

T.illmQues PEARSON

U n lin e resources a va i www.pearsoned.co.in/anitagoel

u


Computer Fundamental by Goel Anita

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