introduction-to-computers-by-peter-norton-6th-ed highlights

SPECIAL [J^ ^ S ix t l^ d it io n
INDIAN
Qe EDITION

INTRODUCTION TO

COMPUTERS

PETER NORTON

In tern S n H T M l

Office

For Sale in India, Pakistan, Nepal, Bangladesh, Sri Lanka and Bhutan only

Information contained in this work has been obtained
by Tata McGraw-Hill, from sources believed to be reli­
able. However, neitherTata McGraw-Hill nor its authors
guarantee the accuracy or com pleteness of any infor­
mation published herein, and neitherTata McGraw-Hill
nor Its authors shall be responsible for any errors,
omissions, or damages arising out of use of this Infor*
mation. This work is published with the understanding
that Tata McGraw-Hill and its authors are supplying in­
formation but are not attempting to render engineering
or other professional services. If such services are re­
quired. the assistance of an appropriate professional
should be sought

m
Tata McGraw-Hill

PET ER NORTON’S * INTRODUCTION TO CO M PUTERS

Indian Adaptation done by arrangement with the McGraw-Hill Companies Inc.. NewYbrk

Sales territories: India. Pakistan, Nepal, Bangladesh, Sri Lanka and Bhutan.

Ninth reprint 2008
RYXDCDRXRB8YA

Copyright (D 2006 by The McGraw-Hill Companies, inc. All rights reserved. No part of this publication may
be reproduced or distributed in any form or by any means, or stored in a database or retrieval system,
without the prior written consent of The McGraw-Hill Companies, Inc.. including, but not limited to, in any
network or other electronic storage or transmission, or broadcast for distance learning.

Some andllaries, including electronic and print components, may not be available to customers outside the
United States.
ISBN-13:97S4M>7-0S9374*9
ISBN -1 0 :0-07-059374-4
Published by the Tata McGraw-Hill Publishing Company Limited.
7 W est Patel Nagar, New Delhi 110 008. typeset mTim es at Script Makers.
19, A1-B. DDA Market, Pashchim Vlhar, New Delhi 110 063 and printed at
Pashupati Printers, 1/429/16, G ali No. 1, Friends Colony. G.T. Road, Shahdara, Delhi 110 095

Cover Printer: SD R Printers

Cover Design: Kapil Gupta

TheM cG raw -H illContponies Ez&

sscr

PH M TPM TQ AT A ClI

Chapter 1: Introducing ComputerSystems 2 Chapter0: Working in the Online World 330

Lesson 1A: Exploring Computersand Their Uses 3 Lesson 9A: Connectinq to the Internet 331
Lesson IB : Lookina Inside the ComputerSvstem 24 Lesson 9B: Doinq Businessin the Online World 345

Chapter 2: Interaction with YourComputer 48 Chapter 10:Workinq with Application Software 382

Lesson 2A: Using the Kevboard and Mouse 49 Lesson 10A: Productivity Software 263
Lesson 2B: Inputting Data in OtherWavs 68 Lesson 10B: Graphics and Multimedia 383

Chapter 3: Secinq, Hearing,and Printin') Data 88 Chapter 11: Database Management 400

l>ctnn 3A; Virfpo and Snunri 89 Lesson 11A: Database Manaqement Systems 401
Lesson 3B: Printinq 107 Lesson 11B: Survey of DatabaseSystems 42Q

Chanter 4: Processing Data 124 Chanter 12:Software Proaramminq 438
Lesson 4A: Transfbrmina Data into Information 439
Lesson 4B: Modem CPUs 12S and Development 456
Ufi Lesson 12A: Creating Computer Proqrams
Chapter5;Storina Data 478
Lesson SA: Types of Storaqe Devices Lesson 12B: Proaramminq Lanauaoes and the
Lesson SB: Measurinq and Improving Proqramminq Process 477
Drive Performance m 497
518
Chapter6: Usina Ooeratinu Systems m Chanter 13: Protectina YourPrivacy. 528
Lesson 6A: Oporatinq Svstem Basics 107 YourComputer, and YourData 532
lesson 6B: Survev of PCand Network 538
Operatino Systems Lesson 13A: Understanding the Need for SS8
Security Measures
Chanter 7: Networks 204 Lesson 13B: Takina Protective Measures
Lesson 7A: Networkinq Basics 205
Appendix A: Creating YourOwnWeb Paae

22k Appendix B: Buyinq YourFirst Computer

Appendix C: ComputerViruses
242
Annendix D: History of Microcomputers

243 Appendix E: Self-Check Answers
267

Chapter& Presenting the Internet 284

Lesson 8A: The Internet and the World 286
Lesson 8B: E-Mail and Other Internet Services 312

Urheberrechtlich geschutzies ^ aterial

FEATURE ARTICLES

At Issue Productivity Tig

Computerized Oisease Manaqement 36 Choosinq the Riqht Toolfor the Job 12
Computer Votinq—Is It a Good Thinq?
62 Savinq Time with Keyboard Shortcuts 60
Digital Student Portfolios
Controllinq Computers with the Mind 10? The Care and Feedinq of Printers 114

Stompinq Out Spam 134 DoYou Need Mnn>RAM? 140
On the Beat with Techno-Cops
Who Reallv Ownsthe Software on Your PC? 192 Backino Up Your Data 174
Ptav Ball! Baseball Enters the Information Aqe
Hot and Oh-So-Cool: Technoloqv Forecasts 228 Do-It-YourselfTech Support 214
the Weather
Software Piracy 252 The Telecommuter's Checklist---------------- — 220

316 Evaluatino the Reliability of Search Results

336 and Web Sites JQ4

372 Sharinq an Internet Connection 340

414 Automatinq YourWork with Macros 376

0ataha<e Macros 4?fi

450 Findinq Faster Alqorithms 448
490 Keepinq YourPC Up to Date 486

Norton Notebook Computers In YourCareer 40
7R
The Merqinq of Media and Meaning 18 Usinq Computers Outside of the IT Industry
Speech Recoqnition 74 HanfaMiv Technician 116
Flat Video Is Anvthinq But 98 ComputerTraininq Specialist 156
What Is a ComputerChip? 150 ComputerSales Professional 194
Lookinq Back, Movinq Forward 180 Careers in Outsourcinq 234
Chanqinq Your PCs Operatinq System 198 Help Desk and Technical Support Specialists 276
Fiqhtinq Hackers 260 Careers in Networkinq 322
Internet Time Travel: The Wayback Machine 294 Documentation and Online Help System Desiqner 354
Business, the Internet and Everything 352 Career Opportunities and the Internet 392
Whv Own When You Can Rent? 390 Careers in Multimedia 430
406
Artificial Intelligence: W ill Computers Ever Think? 468
Nexus: Converqinq Technologies 466 Careers in Proqramminq 510
506 ComputerScientist

X
Urheberrechtlich geschutztes Material

nONTFNTS

data 25
26
Introducing Computer Systems 2- IkoK 26
22
Chapter Contents The Information Processing Cycle 28
2 22
I »«nn 1A; 21
Essential Computer Hardware 22
Exploring ConHHiters and Their U m 20
Processing Devices 21
Overview: Computers in OurWorld 21
The Computer Defined 3_ Memory Devices 32
Computers for Individual Users 22
3- RandomAccess Memory 23
Desktop Computers 4 Read-Only Memory 33
Workstations 5 Input and Output Devices 24
Notebook Computers 5 Storage Devices 28
Tablet PCs Magnetic Storage 28
Handheld PCs 8 Optical Storoqe 28
Smart Phones 22
Computers for Organizations 8 Software Brings the Machine to Life
Network Servers 40
Mainframe Computers Z System Software 42
Minicomputers 7 Application Software 48
Supercomputers 1 Computer Oata 48
Computers in Society 8 At Issue: Computerized Disease Management 42
Productivity Tip: Choosing the Right Tool 8 Computer Users 42
for the Job 9 The User's Rote 42
Why Are ComputersSo Important? 10 “Usertess*Computers
Horn# 10 Computers In Your Careen Using Computers 48

Education 11 Outside of the IT Industry 49
42
SmaUBusiness Lesson IB Review SO
Industry 12 Chapter Skills Review SO
Government 12 5fl
Health Care V r Chapter Labs 42
Norton Notebook: The Merging of Media
and Meaning IS ­ __ Discussion Questions
Lesson 1A Review IS . Research and Report
16. Ethical Issues
Lesson 1 B ;
Looking ln>ld» the Computer System 12

Overview: Dissecting the Ultimate Machine 18 C H A P T E R 2::
The Parts of a ComputerSystem
18 Interacting with Your Computer
Hardware 20
Software Chapter Contents

lp «n n 8 8 ;

Using the Keyboard and Mouse
24

Overview: The Keyboard and Mouse
24 The Keyboard
25 The Standard Keyboard Layout
25 TheAlphanumeric Keys

25 _____ TheModifierKeys

xl
Urheberrechllich geschut

The Numeric Keypad 51 Chapter Labs 84
TheFunction Keys R5
TheCursoi'MovementKeys 51 DisnK<fon AtiPctfnnc
Soeciol-Purpcse Keys 85
How the Computer Accepts Input from 52 Research and Report 85
the Keyboard 52 Ethical Issues
The Mouse
Usina the Mouse 53 C H A PTER 3;:
Mouse Button Configurations 54
Variants ofthe Mouse 56 Seeing. Hearing, and Printing Data 86
86
Trackpads S3 Chapter Contents
Pointers in the Keyboard
Productivity Tip: Savfnq Time With Keyboard 5ft
Shortcuts
Erqonomics and InDut Devices 58
Repetitive Stress Injuries
Avoidinq Kevboard-Related Injuries 59 Overview: Reachina Our Senses with Siaht and Sound 97
At Issue: Computer Votina—Is It a Good Thinq? 59 Monitors 88
Lesson 2A Review
CRT Monitors 89
Lesson 2 B : ffl) 90
Inputting Data In Other Ways 60 92
93
Overview: Options for Every Need and Preference Other Types of Monitors
Devices for the Hand 61 94
94
Pens Comparinq Monitors
Touch Screens 62
Game Controllers
Optical Input Devices S in
Bar f«do RparhifS
Jmaqe Scanners and Optical Character 62
Recoqnition (OCR)
Norton Notebook: Speech Recoqnition Refresh Hate 99
Audiovisual Input Devices Dot Pitch
Microphones 96
Other Types of Audio Input
Video Input Virion farrfe 96
Digital Cameras 68 97
Computers In Your Careen Hardware Technician 97
Lesson 2B Review Erqonomics and Monitors 98
Chapter Skills Review 68 Eyestrain 98
69 Norton Notebook: Rat Video Is Anvthina But 100
xll Contents 69 Electromaqnetic Fields 100
100
70 Data Projectors 102

70 Sound Systems
71 Sound Cards

71 Headphones and Headsets

At Issue: Call of the Wild: Bioaeroustle Research 1ft?
104
72 Lesson 3A Review
74

74 Lesson 311;

*4 P rin tin g 107

76 Overview: Puttina Diqital Content in Your Hands 107
77 Commonlv Used Printers 108
77 Dot Matrix Printers 108
78 Ink Jet Printers 110
an 111
112
Laser Printers

84 All-in-One Peripherals

Urheberrechtlich geschulztes Material

Comparing Printers 112 The Computers Internal Clock E E E E ’S E b b E B b B E E B B B E E B B B E B B E-BSE I E E BB" BSE E
High-Quality Printers
U I The Bus
Phntn Printers
Productivity Tip: The Care and Feeding of Printers m The Data Bus
H it TheAddressBus
Itefmal-Wax Printers m B ,it Storulnirh
Pye-Sublimation Printers 115 Cache Memory
Plotters 116 Productivity Tip: Do You Need More RAM?
Computers In Your Careen ComputerTraining
Specialist Lj»«on 4A Review
L«*mn 3B Review
116
Chanter Skills Review ua Lesson 4 B :
122 Modem C P U s
Chapter labs Owrvipw: The Race for the Desktop
Discussion Questions 122
Research and Report ALflQklfttife.the_P.rMtt}ot
Ethical Issues 123 Microcomputer Processors

123
Intel Processors
123 Advanced Micro Devices (AMD) Processors

CHAPTER 4” FwxkmIi* Processors
Processing Data
124 Comparing Processors
Chapter Contents
iik Norton Notebook: What Is a Computer Chip?

Lesson 4 A : RISC Processors
Transforming Data into Information
125 Parallel Processing
Overview: The Difference between Data Extending the Processor's Power to Other Devices
and Information
How Computers Represent Data Standard Computer Ports
125
Number Systems
Bits and Bytes Serial and Parallel Ports
Text Codes 126 Specialized Expansion Ports
How Computers Process Data 12&
The CPU
SCSI
The Arithm etic Lode Unit 122 USB
12Z IEEE 1394 (FirtWirt)
12& Musical Instrument Dtoitot Interface (MIDI)
130 Expansion Slots and Boards
m Computers In Your Career: Computer Sales
ua

Machine Cycles 130 e cia a b L
Memory 131 Plug and Play
132
Volotilt Memory U2 Lesson 4B Review
132.
Factors Affecting Processing Speed Chapter Skills Review
Registers 133
133 Chapter labs
At Issue: Cyborgs Among Us: Wearable Technology 134 Discussion Questions
Memoryand Computing Power____________ 134 Research and Report
Ethical Issues

Contents

CHAPTER 5:: At Issue; Digital Student Portfolios______________ 192
Storing Data
164 Orive-Interface Standards 192
Chapter Contents
164 Enhanced Inteqrated Drive Electronics (ODE) 193
Lesson 5A:
165 Small Computer System Interface (SCSI) 193
Types of Sto rag e D evices
165 USB and FireWire 194
Overview: An Ever-Growinq Need 166
Cateoorizing Storage Devices 166 Computers In Your Careen Careers in Outsourdna 194
Maqnetic Storage Devices 166
168 Lesson SB Review 196
How Data Is Stored on a Disk
How Data Is Orqanized on a Maqnetic Disk 168 Chapter Skills Review 200

Troekt andStcton 170 Chapter labs 200
How the Operatinq System Finds Data on a Disk 171 Discussion Questions ?01
Diskettes (Floppy Disks) 173 202
Hard Disks 173 Research and Report ?0?
Removable Hiqh-Caparitv Maqnetic Disks 174 Ethical Issues
Tape Drives 174
Productivity Tip: Bacldnq Up Your Data 175 C H A P T ER 6 :: 204
Optical Storaqe Devices 176 Usinq Operatinq Systems
CO-ROM 177 204
DVD-ROM 17S Chapter Cpntents
Recordable Optical Technologies 179 205
Solid-State Storaqe Oevices 179 Lesson 6A:
Flash Memory 180 205
Norton Notebook: Looking Back, Moving Forward 1RO Operating System Basics 206
Smart Cards 182 20$
Solid-State Disks 183 Overview: The Purpose of 0Derating Systems 206
Lesson 5A Review 2Q$
1B7 Types ofOperalinq Systems 207
Lesson 5 B : 208
M easuring and Im proving D rive 187 Real-Time Operating Systems 208
Perform ance 188 ?11
1M Sinqle-User/Sinqle-Taskinq Operatinq Systems 212
Overview: The Need for Speed 189 213
Averaoe Access Time 189 Single-User/Multitaskina Operating Systems 214
Data Transfer Rate 190 215
Optimizing Disk Performance 190 Multi-User/Multitasking Operatinq Systems 216
190 216
Cleaning Up Unneeded Files Providing a User Interface 216
Scanninq a Disk for Errors 217
Defiraqmentinq a Disk Graphical User Interfaces ?17
File Compression 217
Command-Line Interfaces 217
217
Running Programs

Sharing Information

Productivity Tip: Do-It-YourselfTech Support

Managing Hardware

Processing Interrupts

Workinq with Device Drivers

Enhancing an OSwith Utility Software

Backup Utilities

Antivirus ‘

Firewall
Intrusion Detection
Screen Savers

xiv Contents

Urheberrechllich geschutztes Material

Norton Notebook: Changing Your PCs Overview: Sharing Data Anywhere, Anytime__________ 243
Operating System__________________________
218 The Uses of a Network 244
I m m " 6A Review___________________ 220 Simultaneous Access 244

Lesson 6 B; Shared Peripheral Devices 245

S u rv e y o f P C a n d N etw o rk Personal Communications 246
O p e ra tin g S y s te m *____________________
224 Easier Data Backup 247
Overview: Operating Systems Yesterday and Today 224 Common Tvpes of Networks 248
PC Operating System*________________________ 248
Local Area Networks (LANs)
DOS____________________________________
Window* NTWorkstation___________________ 225 Wide Area Networks (WANs) 248
Windows Qx_____________________________ 225 Hybrid Networks 248
Windows 2000 Professional________________ 225 Campus Area Networks (CANs) 249
Windows XP_____________________________ 226 Metropolitan Area Networks (MANs) 249
The Macintosh Operating Svstem____________ 228 Home Area Networks (HANs) 249
UNIX for the Desktop_____________________ 228 Intranets and Extranets 249
Linux for the Desktop
At Issue: Controlling Computers with the Mind 229 Hnw Networks Are Structured 250
Network Operating Systems___________________ 229 Server-Based Networks 250
Windows NT Server_______________________ 229 Client/Server Networks 250
Windows 7000 Server_____________________ 230 Peer-to-Peer Networks 251
Windows Server 2003_______________________ 230 At Issue: Catching 'Cvberslackers' on the Job 252
Novell NetWare__________________________
1IMTX for Servers_________________________ 231 Network Topoloqies and Protocols 253
232 255
lim a for Servers_________________________ 255
Embedded Operating Systems_________________ 232 256
Computers In Your Career: Help Desk and 256
Technical Support Specialists_______________ 232 256
Imtton 6B Review_________________________ 256
233 Network Hardware 258
Chapter Skills Review______________________ 233 NetworkInterface Cards (NICs) 260
233 NetworkIMrioq Devices 261
Chapter Labs____________________________ 263
Qisnission Questions_____________________ Cabling Equipment
Research and Report_____________________
Cthical Issues___________________________ 234 Norton Notebook; Fighting Hackers
236 Protocols
C H A PTE R 7 :: 240 lesson 7A Review
Networks________________________
240 Lesson 7 B ; 267
Chapter Contents__________________________ 241 267
241 D a ta C o m m u n icatio n s
Lesson 7A: 241 268
Overview: The Local and Global Reach of Networks 268
N e tw o rk in g B a e lc s ___________________ 242 Oata Communications with Standard Telephone 270
|ine< and Modems 270
242 271
Modems 272
243
Ih et for a Modem
Productivity Tip: The Telecommuter's Checklist

Using Digital Data Connections
Rmadhand Connections

Contents

DSL Technotoaks 272 Getting Help with Your Browser 299
271 Searching the Web 299
H tvietn riuuw tinn*_______________ 301
274 Using a Directory 301
em___________________________ Using a Search Engine 302
303
Wireless Networks_____________________________ -21k UsinoBoolean Operators in Your Searches
UsinoAdvancedSeo'ch Options 304
Wireless; 802,11____________________________ -222 Productivity Tip: Evaluating the R eliability of 306
Search Results and Web Sites 306
_22SWireless Access Point_______________________ Using a Metasearch Engine 307
Sponsored versus Nonsponsored Links 308
Wireless Adapter 27S Using Site-Specific Search Tools
L#cuui BA Review 312
Computers In Your Careen Careers in Networking 276
1» « n n ftB ? 312
711Review____________________________ 278 E-M ail an d O th e r In ta m a t S e rv ic e s 313
313
Chapter Skills Review_________________________ 282 a i*
314
Chapter Labs_______________________________ 282 314
rW im ifin Questions________________________ _283 314
Research and Report________________________ 283 315
Ethical Issues______________________________ 316
317
C H APTE R 8 :: 284 Overview: Communicating Through the Internet 317
Presenting the Internet_____________ Usinq E-Mail 317
284 319
Chapter Contents_____________________________ Understanding E-Mail 320
285 321
Lesson B A : Ustserv Systems 321
T h e In te rn a l a n d .lh a .W flrid .M fld a .W eh _ _2&S Using an E-Mail Proqram 322
286
Ov£ivi£w:.yyhat Is the Internet?_________________ 286 Creatinqa Message 322
The Internet's History_________________________ 287 ReceivingandReadinga Menage 324
288 At Issue: Stomoing Out Soam 328
The Beginning: A "Network of Networks'*_______ 288 Using Web-Based E-Mail Services
Today; Still Growing________________________ 328
The Internet's Major Services___________________ _J2Q FTP 329
Understanding the World Wide Web______________ Internet Relav Chat (IRC) and Web-Based Chat 329
How the Weh Works_________________________ _221 Instant Messaging 329
Web Browsers and HTML Taos_________________ Online Services
URLs_____________________________________ 292 Peer-to-Peer Services
Helper Applications and Multimedia Content Computers In Your Careen Documentation and
Norton Notebook: Internet Time Travel: 294 Online Help System Designer
The Wayback Machine 295 Lesson 8B Review
Usino Your Browser and the World Wide Web______ 296 Chapter Skills Review
launching Your Browser 296 Chapter Labs
Navigating the Web 296 Discussion Questions
297 Research and Report
Using URLs 298 Ethical Issues
Usino Hvoertinks_______________________________
Using th e Browser's N anoathn Took_____________
Closing Your Browser________________________

xvl Contents

Urheberrechllich g eschutztes Material

CHAPTER 9:: 330 Security 354
Working in the Online World_________
330 Chapter Skills Review 360
Chapter Contents_____________________________ Chapter Labs 360
£31 Discussion Questions 361
Lesson 9 A ; Research and Report
C o n n e ctin g to th e In te rn e t_____________ 331 tfl
332 CHAPTER lO::
Overview: Joining the Internet Phenomenon 332 Working with Application Software Ml
Connecting to the Internet through Wires________ 332
333 Chapter Contents 362
Dial-up Connections________________________ 333
High-Speed Broadband Connections 334 Lesson 10A: 362
334
IntegratedServices DigitalNetwork (1DSN) Service 33S Productivity Software 363
DigitalSubscriberline /DSL) Services___________ 33S Overview: Software to Accomplish the Work of Life 363
CableModemService 336 Acguiring Software 364
How PC Applications Access the Internet 336 ?6 i
Connecting to the Internet Wirelessly 338 Freeware and Public Domain Software 364
Wireless WAN (WWAN) Connections 340 Open-Source Software 365
At Issue: On tin Beat with Techno-Cops________ 342 Word Processing Proqrams 365
Satellite Sorvires___________________________ 366
WLAN Connections
Productivity Ho: Sharing an Internet Connection
Lesson 9A Review

Lesson 9 B : 343 Entering and Editing Text 366
D oing B m ln e w In th e O n lin e W o rld 34S Formatting Text 367
Spreadsheet Programs 368
Overview: Commerce on the World Wide Web______ _24fi The Spreadsheet's Interface 368
346 Entering Data in a Worksheet 369
E-Commerce at the Consumer Level______________ 347 Presentation Programs 371
Online Shopping___________________________ 347 At Issue: Who Really Owns the Software
Online Stores versusPttvskotLocations_________ 348 on Your PC? 372
UsingOnline Catalogs______________________ 349 The Presentation Proqram's Interface 372
Paying forPurchases_______________________ 349 Creating a Presentation 374
Getting Customer Service 350 Presenting Slide Shows 375
Online Banking and Finance Productivity Tio: Automating Your Work
OntineBanking___________________________ _350 w ith Macros 376
350 Personal Information Managers 376
fcttin* Finttnr*____________________ 3S1 Lesson 10A Review 379

f-fnmmpiTp at the Business Level_______________ 352 Lesson 1 Q B ; 383
_352 381
Business-to-Business (B2B) Transactions______ Graphics and Multimedia 384
Intranets and Extranets_____________________ 354
Norton Notebook; Business, the Internet Overview: Graphics. Graphics Everywhere
and Everything______________________________ Understanding Graphics File Formats
Telecommuters____________________________
Computers In Your Careen Career Opportunities
and the Internet

Contents xvH

Bitmap and Vector Graphic 384 At Issue: Play Ball! Baseball Enters the 414
File Formats and Compatibility Issues 386 Information Age 416
Gettinq Imaqes into Your Computer 386
Graphics Software 387 Survey of Database Systems 420
Paint Programs 387 Overview: When Applications Grow Huoe 420
Draw Programs 387 Enterprise Software 421
Photo-Editinq Proqrams 388 421
Computer-Aided Design Proqrams Meeting the Needs of Manv Users 423
3-0 and Animation Software 390 Databases at Work 423
Norton Notebook: Why Own When You Can Rent? 390 425
Multimedia Basics 392 Databases in Business 425
Computers In Your Careen Careers in Multimedia 394 Databases on the Internet 426
Lesson 10B Review 397 Databases for Individuals 428
397 Productivity Tic: Database Macros 4?fl
Chapter Skills Review 397 Common Corporate Oatabase Manaqement Svstems 429
398 429
Chapter Labs 398 DB2 429
Discussion Questions SQL Server 430
Research and Report 400 MySQL 432
Ethical Issues Computers In Your Careen Database Careers 436
400 Lesson 11B Review 436
C H A P T E R 1 1 :: Chapter Skills Review 436
Database Management 401 Chapter Labs 437
Discussion Questions 437
Chapter Contents Research and Report
438
Lesson 11 A :
438
Database Management Systems
439
Overview: The Mother of All Computer Applications 401 439
Databases and Database Management Systems 440
402 CHAPTER 12:: 441
The Database 402 441
4tK Software Programming and 442
Th* DBMS Development 442
Norton Notebook: Data Warehouses 405
Workinq with a Database 406 Chapter Contents

Creatinq Database Tables 406 Leccon 1 2 A :
Understanding Field Types
Interim Data in a Table 407 Creating Com puter Program s
407 Overview: What Is a Computer Proqram?
Viewinq Records 409
Sortinq Records
Querying a Database What Is a Computer Proqram?
Generating Reports 409

Hardware/Software Interaction
410

412
Machine Code

*1? Programming Languages

xviH Contents

Compilers and Interpreters 443 Chapter Contents 476

Planninq a Computer Proqram 444 477
How Programs Solve Problems 445 Lesson 1 3 A :
477
Program Control How U nderstanding th e N eed fo r S e cu rity 478
Algorithms 44S 476
478
Productivity Tip: Finding Faster Algorithms 445 47fl
Structured and Object-Oriented Programming 446 Overview: The Need for Computer Security
448 Basic Security Concepts 479
Programming Structures 448 Threats 479
At Issue: Hot and Oh-So-Cool: Technoloav 449 Deqrees of Harm 480
Forecasts the Weather 480
f rtiintM iM iciint 481
Object-Oriented Proqramminq
Lesson 12A Review 4*i0 Threats to Users
450 Identity Theft
Lesson 1 2 B :
452 Loss of Privacy
PubHc Records on the Internet

Program m ing Languages and the 456 Online Sovinq Tools 481
Program m ing Pro ce ss 481
Overview: The Keys to Successful Proqramminq 456 WebBum 482
The Evolution of Proqramminq Lanquaqes 457 Sowrott
457 Spam 483
Cateqories of Proqramminq Lanquaqes 458 Computer-Related Injuries 484
458 m
Hiqher-Level Languages 459 Power-Related Threats 485
Third-Generation Languoges 460 Theft and Vandalism 485
Fourth-Generotion Lanwooes 461 Natural Disasters 486
461 Productivity Tip: Keepinq Your PC Up to Date 486
World Wide Web Development Lanquaqes 488
c r. »? . i

The Systems Development Life Cycle for Proqramminq 465 Malware. Viruses, and Malicious Proqrams 488
488
Norton Notebook: A rtificial Intelliqence: Cybercrime 489
Hocking 489
W ill Computers Ever Think? 466 Common HockingMethods 490

Computers In Your Careen Careers in Proqramminq 468 At Issue: Software Piracy 492
Cyberterrorism 422
Lesson 12B Review 470

474

Chapter Labs 474

Discussion Questions 475 Lesson 1 3 B : 497
Research and Report 475 Taking P ro te ctive M easures
Ethical Issues 475 497
Overview: Keepinq Your Svstem Safe 498
C H A P T E R 13:: 476 Protecting Yourself 498
ProtectingYourPrivacy,Your Computer, 498
and Your Data Avoidinq Identity Theft 499
Monoaino Your Papers
Guarding Personal Information

Contents **x

looting a t the Big Picture 499 Lesson 13B Review 512
Chapter Skills Review 516
Protect!nq Your Privacy 499 516
Chapter labs 516
Keeping Marketers at Bov 499 Discussion Questions 512
Research and Report 512
Knowing YourRights 500 Ethkal Issues
Appendix A: 518
Manaqinq Cookies, Spyware, and Other *Buqs" 501 Creating Your Own Web Page
Appendix B: 526
Dealinq with Cookies 501 Buying Your First Computer
532
Removing Web Bugs end Spyware 502 Appendix C:
Computer Viruses 538
Evadinq Spam 502 Appendix D:
History of Microcomputers 558
Keeoinq Your Data Secure 503 fiSS
Appendix E: 591
Restricting Access to Your System 504 Self-Check Answers 593

Lim iting PhvskalAccess 504 Glossary

Using a Firewall 505 Photo Credits

Backing Up Data 505 Index

Norton Notebook: Nexus: Converging Technologies 506

Safeguarding Your Hardware 508

Using Automated Warnings 508

Handling Storaae Media 508

Storing Computer Equipment 509

Keeping Your ComputerClean 509
Computers In YourCareen ComputerScientist 510

xx Contents

Urheberrechtlich geschutztes Material

PREREQUISITES

W hat You Should Know Before Using
This Book

This book assumes that you have never used a computer before or that your com­
puter experience has been very brief. If so, you may need to leam some basic com­
puter skills before proceeding w ith this course. This Prerequisites section
introduces basic skills, using illustrations to help you recognize and remember the
hardware or software involved in each skill. Some o f these skills are covered in
greater detail in other units of this book. In such cases, you w ill find references
that point you to more inform ation.

Equipment Required forThis Book's Exercises

» IBM-compatible personal computer
» Keyboard
» Two-button mouse
» Windows 98 or higher
» Internet connection
» Web browser

Turning the Computer On and Off

Turning the Computer On

As simple as it may sound, there is a right way to turn a computer's power on and
off. If you perform cither of these tasks incorrectly, you may damage the com­
puter's components or cause problems for the operating system, programs, or
data files.

1. Before turning on your computer, make sure that all the necessary cables (such
as the mouse, keyboard, printer, modem, etc.) are connected to the system
unit. Also make sure that the system’s power cords are connected to an ap­
propriate power source.

2. M ake sure that there arc no diskettes in the computer's diskette drive, unless
you must boot (he system from a diskette. (The term booting means starting
the computer.) If you must boot the system from a diskette, ask your instruc­
tor for specific directions.

3. Find the On/Off switch on
each attached device (the
monitor, printer, etc.) and
place it in the O N position.
A device's power switch
may not be on the front
panel. Check the sides and
back to find the On/Off
switch if the swirch is not
located on the front panel.

: : F a more Inform ation on 4. Find the On/Off switch on the computer’s system unit—its main box into
which all other components are plugged— and place it in the O N position.
Windowsand otheroperating
systems, see Chapter6. M ost computers take a minute or two to start. Your computer may display
*Using Operating Systems." messages during the start-up process. If one of these messages prompts you to per­
form an action (such as providing a network user ID and password), ask your in­
structor for directions. After the computer has started, the Windows desktop w ill
appear on your screen.

Turning the Computer Off

In Windows-based systems, it is critical that you shut down properly, as described
here. Windows creates many temporary files on your computer's hard disk when
running. By shutting down properly, you give Windows the chance to erase those
temporary files and do other “ housekeeping” tasks. If you sim ply turn off your
computer while Windows or other programs are running, you can cause harm to
your system.

Note: The illustration shows the shut-down process in Windows 98. The
process, menus, and dialog boxes arc the same in a ll versions of Windows except
Windows XP, as noted in die following instructions.

1. Remove any disks from the diskette and CD-ROM drives and make sure that
a ll data is saved and a ll running programs are closed. (For help w ith saving
data and closing programs, ask your instructor.)

2. Using your mouse pointer; click the Start button, which is located on the
taskbar. The Start menu w ill appear On the Start menu, click Shut Down. (If
you use Windows XP, click the Tum O ff Computer option.) The Shut Down
Windows dialog box w ill appear. (In Windows XP, the Tum O ff Computer di­
alog box w ill appear.)

ThebackgroundIs called
the desktop.

Iconsare picturesthat
representprograms,files,
disks,andoilier resources
onyourcomputer.

turn off the computer. opentheStart menu. Youusethe mousepointerto
xxil Prerequisites access resourcesbycSdong
Icons and commands.
The Taskbarshowsyou viha!
programsare currentlyrunning
onyourcomputer.

:nui M

Windows w ill begin the shut-down process. Windows may display 13
a message telling you that it is shutting down. Then it may display the
message “ It is now safe to turn off your computer.” When this message M m nw iW M id
appears, turn o ff the power to your system unit, monitor, and printer.
LjsslJ.
In some newer computers, the system unit w ill power down auto-
m atically after Windows shuts down. If your computer provides this go oo
feature, you need to turn off only your monitor and other devices.
-
Using the Keyboard jq ,o :o o o q

If you know how to type, then you can
easily use a computer keyboard. The
keyboard contains a ll the alphanumeric
keys found on a typewriter; plus some
keys that perform spccial functions.

1. In Windows, the en t er key performs 1 -
two prim ary functions. First, it lets -
you create paragraph (“ hard’*) re*
turns in application programs such as " Thekeyboardis covered in detail
in Lesson 2A ‘Using the Keyboard
word and M ouse.'
processors. Second, when a dialog
box is open, pressing e n t e r is like
clicking the OK button. This accepts
your input and doses the dialog box.

2. The sh u t , CTRL (control), and ALT (al­
ternate) keys arc called modifier keys.
You use them in combination w ith other keys to issue commands. In many
programs, for example, pressing CTRL+S (hold the CTRL key down while press*
ing the s key) saves the open document to disk. Used with all the alphanumeric
and function keys, the modifier keys let you issue hundreds of commands.

3. In Windows programs, the ESC (escape) key performs one universal function.
That is, you can use it
to cancd a command before it executes. When a dialog
box is open, pressing ESC is like clicking the CANCEL
button. This action closes the dialog box and ignores
any changes you made in the dialog box.

4. Depending on the program you are using, the function

keys may serve a variety of purposes or none at all.
Function keys generally provide shortcuts to program
features or commands. In many Windows programs,
for example, you can press F l to launch the online help
system.

5. In any Windows application, a blinking bar—called
the cursor or the insertion point—shows you where the
next character w ill appear as you type. You can use the
cursor-movement keys to move the cursor to different

H ifr] m M4.
FI |
« [f6 | ;F71 rb | F9

Prerequisites xxtlf

positions. As their arrows indicate, these keys let you move the cursor up,
down, left, and right.

6. The DELETE key erases characters to the right of the cursor. The BACKSPACE key
erases characters to the left o f the cursor. In many applications, the h o m e and
END keys let you move the cursor to the beginning or end of a line, or farther
when used with a m odifier key. PACE UP and PACE d o w n let you scroll quickly
through a document, moving back or ahead one screcn at a time.

*■ I amwhat I am. ■Cursor(orinsertion point)

[jj ■Cursor-movementkeys Using the Mouse
-*■t
The mouse makes your computer easy to use. In fact, W in­
Backspace till H|C•• 1I dows and Windows-based programs are mouse-oriented,
key meaning their features and commands are designed for use
M bw I1 w ith a mouse.

1. This book assumes that you are using a standard two-
button mouse. Usually, the mouse’s left button is the pri­
mary button. You click it to select commands and
perform other tasks. The right burton opens special
“ shortcut menus," whose contents vary according to the
program you are using.

2. You use the mouse to move a graphical pointer around
on the screen. This process is called pointing.

3. The pointer is controlled by the mouse's motions across
your desktop’s surface. When you push the mouse for­
ward (away from you), the pointer moves up on the
screen. When you pull the mouse backward (toward
you), the pointer moves down. When you move the
mouse to the left or right, or diagonally, the pointer
moves to the left, right, or diagonally on the screen.

: : Themouse is covered In greater O Whenthemousemoves..
detailin Lesson2A, U sing the
Keyboardand M ouse.' © -the roJiino mouse
bal spinstne radars.
xxiv Prerequisites
Q Theinformationfromthe
spinning rollers is sentto
the system software,which
controls the pointet

4. To click an object, such as an icon, point to it on the screen, then quickly press "dickcflck"

and release the left mouse button one time. Generally, clicking an object selects
it, or tells Windows that you want to do something with the object.

5. To double-click an object, point to it on the screen, then quickly press and re­
lease the left mouse button twice. Generally, doubleclicking an object selects
and activates the object. For example, when you doubleclick a program’s icon
on the desktop, the program bunches so you can use it.

6. To right-click an object, point to it on the screen, then quickly press and re­
lease the right mouse button one tim e. Generally, right-clicking an object
opens a shortcut menu that provides options for working w ith the object.

7. You can use the mouse to move objects around on the screen. For example,
you can move an icon to a different location on the Windows desktop. This
procedure is often called drag-and-drop editing. To drag an object, point to it,
press and hold down the left mouse button, drag the object to the desired lo­
cation, then release die mouse button.

Prerequisites xxv

U rheberrechtlich ge sc h u tz te s M e erial

Effective Learning Self-check quizzes keep

Tools ttAhe____se_^tst1tn1u_cd!ie_rnutsnaeenrgsaiagneadi1nnagInId

This pedagogically rich book is de­ of the lesson topics.
signed to make (earning easy and
enjoyable. It w ill help you develop
the skills and criticalthinking abil-
itaes that will enable you to under­
stand computers and computer
technology, troubleshoot prob­
lems. and possiblylead you into an
IT career.

Each chapter includes. . . Productivity Tips, Computers In YourCareer, and
other feature articles offer students a more in-depth
» Learning objectives that set measurable goals for discussion of today's technology and how it affects
(esson-by-lesson progress their everyday lives.

» Illustrations that give you a clear picture of the
technologies

» More review materials at the end of each
chapter and lesson: Keyterms quiz, multiple
choice questions, shortanswer review questions,
lab activities, discussion questions, research and
report assignments, and ethical issue discussions

Urheberrechllich geschutzles Material

Each chapter contains two Im portant
lessons—each lesson offers
end-of-chapter quizzes that Technology
engage students in the topics
at hand. Concepts

This book is foil of detailed IT Information technology (IT ) offers
concepts and current photographs many career paths leading to occu­
of the latest technologies.----- pations in such fields as PC repair
Norton Online sidebars point network administration, telecom­
students to the new munications, Web development,
Norton web site graphic design, and desktop sup­
accompanying this 1 port. To become competent in any
textbook where IT field you need certain basic
students can find computer skills. Peter Norton's In-
more information txoduction to Computers, 6e, builds
on IT-specific a foundation for success in the IT
topics. field by introducing you to funda­
mental technology concepts and
giving you essential computer
skills.

Your IT career starts here!

» Self-check qu ints in each lesson
(two per chapter) help students
apply their knowledge as they work
through the lesson

Feature articles

» Norton Notebooks offer insightful
thoughts aboutemerging
technologies and computers in our
society.

» At Issue articles spotlight trends in
information technology and offer a
compelling look at how technology
is used to help people enhance their
lives.

» Computers In Your Career offer
v students a "human face* into IT

professions by providing IT
interviews and ideas for where an IT
career might take today's students.

» Productivity Tips coyer topics such
as adding RAM, printer maintenance,
and sharing Internet connections.

U rh e b e rre ch schOtztes Material

Urheberrechtllch geschutzles Material

OS 07 Introducing
Computer
Systems

CHAPTER CONTENTS ::

This chapter contains the following lessons:
Lesson 1A:
Exploring Computers and Their Uses
» The ComputerDefined
» Computers for Individual Users
» Computers for Organizations
» Computersin Society

Lesson 1Bt
Looking Inside the Computer System
» The Parts of a ComputerSystem
» The Information Processing Cyde
» Essential Computer Hardware
» Software Brings the Machine to Life
» Computer Data
» Computer Users

Overview: Com puters in Our World ■■

Consider this sentence: “ Computers arc everywhere." Does it sound LESSON // 9
like an overstatement? A cliche? N o matter how you perceive the im­
pact of computers, the statement is true. Computers are everywhere. In Exploring
fact, you can find them in some preny unlikely places, including your Computers and
fam ily car, your home appliances, and even your alarm clock! Their Uses

In the pasr two decades, computers have reshaped our lives at home,
w ork, and school. The vast m ajority of businesses now use computer­
ized equipment in some way, and most companies arc networked both
internally and externally. M ore than half of a ll homes in the United
States have at least one computer, and most of them are connected to
the Internet. Workers who once had little use for technology now inter­
act with computers almost every minute of the workday.

This lesson examines the many types of computers that arc in com­
mon use today. Although this class w ill focus on personal computers
(the ones that seem to sit on ever}' desktop), you w ill first learn about
the wide variety of computers that people use, and the reasons they
use them. As your knowledge of computers grows, you w ill understand
that a ll computers— regardless of their size or purpose— arc basically
sim ilar.That is, they all operate on the same fundamental principles, are
made from the same basic components, and need instructions to make
them run.

O B J E C T I V E S ::

In basic terms, define the word
com puter.

Discuss various ways computers
can be categorized.

Identify six types of computers
designed for individual use.

Identify four types of computers
used primarily by organizations.

Explain the importance of
computers in today's society.

Describe how computers are used
in various sectors of our society.

Urheberrechllich g eschutzles Material

ONLINE The Computer Defined

For moreInformationon $glta! In basic terms, a computer is an electronic device that processes data, converting
cwroutors. anetog computers, it into inform ation that is useful to people. Any computer—regardless of its
and»e hisloryd computers,vtsK type—is controlled by programmed instructions, which give the machine a pur­
http://www.mhhc.com/ pose and tell it what to do.
petemorton.
The computers discussed in this book—and which are everywhere around you—
FIG U RE 1A.1 arc digital computers (see Figure 1A.1). As you w ill team in Chapter 4, “ Processing
Thepersonalcomputeris an e» D ata," digital computers are so called because they work “ by the numbers." That
ofa digitalcompute. is, they break all types of information into tiny units, and use numbers to represent
those pieces o f information. Digital computers also work in very strict sequences of
FIG U RE 1A.2 steps, processing each unit of information individually, according to the highly or­
This early analogcompiler, created by ganized instructions they must follow.
VameiarBushInthelate 1920s.was
caBeda *flrtfcrent)alanalyzer.*Itused A lesser-known type of computer is the analog computet; which works in a very
electric mows,gears,andothermoving different way from digital computers. The
pansto sotra equations. earliest computers were analog systems, and
today's digital systems owe a great deal to
FIG U RE 1A.3 their analog ancestors. Analog and digital
Althoughanalogcomputershavelargely computers differ in many respects, but the
been forgotten, manyof today's most important distinction is the way they
computerscientists grew up usingslide represent data. Digital systems represent
rules—a simplekindof analog data as having one distinct value or another;
computer. with no other possibilities. Analog systems,
4 Chapter 1 however represent data as variable points
along a continuous spectrum of values.
This makes analog computers somewhat
more flexible than digital ones, but not nec­

essarily more precise or reliable. Early analog
computers were mechanical
devices, weighing several tons
and using motors and gears to
perform calculations (see Fig­
ure l A.2). A more manageable
type of analog computer is the
old-fashioned slide rule (see
Figure 1A3).
Computers can be catego­
rized in several ways. For ex­
ample, some computers are
designed for use by one per­
son, some arc meant to be
used by groups of people, and
some are not used by people at
a ll. They also can be catego­
rized by their power, which
means the speed at which they
operate and the types of tasks
they can handle. W ithin a sin­
gle category,computers may be
subcategorized by price, the
types of hardware they con­
tain, the kinds of software they
can run, and so on.

Computers for Individual Users FIGURE 1A.4
Manykinds of computerscan beshared
Most computers arc meant to be used by only one person at a bynuifipto usersbutcan be usedby
time. Such computers are often shared by several people (such onlyonepersonala ttttt.
as those in your school’s computer lab), but only one user can
work with the machine at any given moment (sec Figure 1A.4). FIG U RE 1A.S
Networkingb a toytasklortoday's
The six prim ary types of computers in this category arc computers, especiallyportable systems
thatallow usersto connect to their home
» Desktop computers orofficeevenwhentheyare hawing.

» Workstations ‘ ONLINE

» Notebook computers Formoretnfonnationon
desktopcomputers,vist
» Tablet computers http://iwm.mhhe.com/
petemorion.
» Handheld computers
FIGURE 1A.0
» Smart phones DesktopPCsarea familiaritemIn
homes,schools, and workplaces.
These systems are all examples of personal computers (PCs)—
a term that refers to any computer system that is designed for use by a single per­
son. Personal computers arc also called nticroconipuicr*, because they are among
the smallest computers created for people to
use. Note, however, that the term personal
computer or PC is most often used to describe
desktop computers, which you w ill learn about
in the following section.

Although personal computers are used by
individuals, they also can be connected to­
gether to create networks (see Figure 1AJ ) . In
fact, networking has become one of the most
important jobs of personal computers, and
even tiny handheld computers can now becon­
nected to networks. You w ill learn about com­
puter networks in Chapter 7, “ Networks."

Desktop Computers

The mostcommon type of personal computer is the desktop computer—a PC that
is designed to sit on (or under) a desk or table. These are the systems you sec all
around you, in schools, homes, and offices, and they are the main focus of this
book.

Today's desktop computers are far more powerful than those of just a few
years ago, and are used for an amazing array of tasks. Not only do these ma­
chines enable people to do their jobs with greater ease and efficiency, but they can
be used to communicate, produce music, edit photographs and videos, play
sophisticated games, and much more. Used by everyone from preschoolers to
nuclear physicists, desktop computers arc indispensable for learning, work, and
play (see Figure !A .6 ).

Introducing Computer Systems S

: : FIG U R E 1A.7 uJ 4 L I L-lt t t i n L I IJ1 1I I As its name implies, a desktop com*
ThisdesktopPC lodowsthetraditional lil puter is a full-size computer that is too big
design,with e« montorstackedon(op to be carried around. The main compo­
ol the system unit lLL nent of a desktop PC is the system unit,
which is the case that houses the computer’s
: : F IG U R E 1A.8 critical parts, such as its processing and stor­
ThisdesktopPC hasa "kwef"design,
witha systemunitta t sits upright age devices. There are two common
andcan be placedon either He desk designs for desktop computers. The
or thefloor. more traditional desktop model fea­

FormoreInformationon tures a horizontally oriented system
workstations,vtsit unit, which usually lies flat on the top
http://www.mhhe.com/ of the user’s desk. M any users place
petfmorion.
their monitor on top of the system unit
: : FIGURE 1A.9 (see Figure 1A.7).
Wbrfcstatbn computersare famed by
engineersandrtoslgrerswhoneeda Vertically oriented tower models
high-performancesystem. have become the more popular style
. of desktop system (see Figure
Formoreinformationon
notebookcomputers,visit V 1A.8). This design allows the user
http://wwwjnhhe.com/
pctemorton. to place the system unit next to or
6 Chapter 1 under the desk, if desired.

Workstations

A workstation is a specialized, single-user
computer that typically has more power
and features than a standard desktop PC
(see Figure 1A.9).These machines are pop­

ular among scientists, engineers, and
animators who need a system with
greater-than-average speed and
the power to perform sophisticated

tasks. Workstations often have large,
high-resolution monitors and accelerated graphics-
handling capabilities, making them suitable for advanced archi­
tectural or engineering design, modeling, animation, and video editing.

Notebook Computers

Notebook computers, as their
name implies, approximate the
shape of an 8.5-by-ll-inch
notebook and easily fit inside a
briefcase. Because people fre­
quently set these devices on
their lap, they are also called
laptop computers. Notebook
computers can operate on
alternating current or special bat-
tcrics. These amazing devices gener­
ally weigh less than eight pounds, and
someeven weigh less than three pounds! During use, the computer’s lid is raised to
reveal a thin monitor and a keyboard. When not in use, the device folds up for easy
storage. Notebooks arc fully functional microcomputers; the people who use them
need the power of a full-size desktop computer wherever they go (see Figure
I A.10). Because of their portability, notebook PCs fall into a category of devices

Urheberrechllkrt Mg

called mobile computers—systems small FIG U R E 1A.10 ::
enough to be carried by their user.
Notebookcomputers havethe powerand
Some notebook systems are designed to featuresat desktopPCsbutare(ghtand
be plugged into a docking station, which portable.
may include a large monitor, a full-size
keyboard and mouse, or other devices (see
Figure 1A.11). Docking stations also pro­
vide additional ports that enable the note­
book computer to be connected to
different devices or a network in the same
manner as a desktop system.

Tablet PCs Fa moreWormatonon
tabletPCs.visit
The tablet PC is the newest development http://wrwwjnhhc.can/
in portable, full-featured computers (see petemorton
Figure 1A.12). Tablet PCs offer a ll the
functionality of a notebook PC , but they FIG U RE 1A.11 ::
are lighter and can accept input from a
special pen—called a stylus or a digital pen—that is used to tap or w rite directly Adockingstationcan makea notebook
on the screen. M any tablet PCs also have a built-in microphone and special soft* computerfoolIke a desktopsystem,by
ware that accepts input from the user's voice. A few models even have a fold-out addnga fuB-sfeemonitor,keyboard,and
keyboard, so they can be transformed into a standard otherfeatures.
notebook PC . Tablet PCs run specialized versions of
standard programs and can be connected to a net­ FormoreWormatonon
work. Some models also can be connected to a handheld PCs. vtsE
keyboard and a full-size monitor. http://www.mhhe.com/
petemorton.
Handheld PCs
FormoreWormatonon
Handheld personal computers are com­ smartphones,visit
puting devices small enough to fit in your http://www.mlihe.com/
hand (see Figure 1A. 13). A popular type petemorton.
of handheld computer is the personal
digital assistant (PD A ). A PDA is no FIG U RE 1A.11 ____________
larger than a small appointment book
and is norm ally used for special applica* TabletPCsaregainingin popularity
tions, such as taking notes, displaying telephone numbers and addresses, and amongprofessionalswhoneedtotake
keeping track of dates or agendas. M any PDAs can be connected to larger com­ lots of notes anddeal with hanldrawn
puters to exchange data. M ost PDAs come with a pen that lets the user w rite on documents,suchas architects.
the screen. Some handheld computers feature tiny built-in keyboards or micro­
phones that allow voice input.

M any PDAs let the user access the Internet through a wireless connection, and
several models offer fe a tu re s __________
such as cellular telephones,
cameras, music players, and
global positioning systems.

Smart Phones

Some cellular phones double
as miniature PCs (see Figure
1A.14). Because these phones
offer advanced features not
typically found in cellular
phones, they are sometimes

Introducing ComputerSystems 7

FIG U R E 1A.13 called smart phones. These features can include
Web and c-mail access, special software such as
Devicessuchas POAspuJ a computerin personal organizers, or special hardware
yourpocketandcanbeuseaIn many such as digital cameras or music players.
dtftoronlways. Some models even break in half to reveal a
miniature keyboard.

Computers for Organizations

ONLINE Some computers handle the needs of many
users at the same time. These powerful systems
Formoreinhumationan arc most often used by organizations, such as
neftvak ser»er$. nu businesses or schools, and are commonly found
http://www.inJjhe.com/ at the heart of the organization’s network.
pctcmorton Generally, each user interacts with the computer through his or her own de­
vice, freeing people from having to w ait their turn at a single keyboard and mon­
FIG U R E 1A.14 itor (see Figure 1A.15). The largest organizational computers support thousands
NdwceWar pticres, liketheNokia0500 of individual users at the same time, from thousands o f miles away. W hile some
Communicator, doubtoas tiny computers, of these large-scale systems are devoted to a special purpose, enabling users to
ottering manyof mofeaturesof POAs. perform only a few specific tasks, many organizational computers are general-
purpose systems that support a wide variety of tasks.
FIG U RE 1JL15
In manycompanies,woetersuseIhelr Network Servers
desWcpsystems toaccess a centra!,
sharedcomputer. Today, most organizations’ networks are based on personal computers. Individ­
ual users have their own desktop computers, which are connected to one or more

centralized computers, called network servers. A network server is usually a
powerful personal computer with special software and equipment
that enable it to function as the prim ary computer in the net­
w ork.
PC-based networks and servers offer companies a great deal
of flexibility. For example, large organizations may have dozens
or hundreds of individual servers working together at the heart of
their network (see Figure 1A.16). When set up in such groups—
sometimes called clusters or server farms—network servers may

not even resemble standard PCs. For example, they may be
mounted in large racks or reduced to sm all units called “ blades,"
which can he slid in and out of a case. In these large networks, differ­

ent groups of servers may have different pur­
poses, such as supporting a certain set of
users, handling printing tasks,enabling Inter­
net communications, and so on.

A PC-based server gives users flexibility to
do different kinds of tasks (see Figure I A.17).
This is because PCs are general-purpose
machines, designed to be used in many ways.
For example, some users may rely on the
server for e-mail access, some may use it to
perform accounting tasks, and others may use
it to perform word-processing or database-
management jobs. The server can support
these processes, and many others, while
storing information and programs for many
people to use.

8 Chapter 1

Depending on how the network is set FIGURE 1A.18
up, users may be able to access the server
in m ultiple ways. O f course, most users Large corporatenetwortcscan use
have a standard desktop PC on their desk hundredsof servers.
that is permanently connected to the net­
work. M obile users, however, may be able
to connect a notebook PC or a handheld
dcvice to the network by wireless means.
When they are away from the office, users
may be able to use the Internet as a means
of connecting to the company’s network
servers (see Figure 1A.18).

Mainframe Computers _____________________

Mainfram e computers are used in large

organizations such as insurance compa­ Formoreinformationon
rranframecomputer.visit
nies and banks, where many people fre­ http-y/www.mhhc.com/
petemorton.
quently need to use the same data. In a
FIGURE 1A.17
traditional mainframe environment, each Theseworfcersmaybe connectedto the
same networtc9erver,yetusingIttarvery
user accesses the mainframe’s resources different tasks.

through a device called a terminal (see FIGURE 1A.18
Many userscan access the*
Figure 1A.19). There are two kinds of ter­ organization'snatwoiknomatter
where theygo.
minals. A dumb term inaldoes not process

or store data; it is simply an input/output

(I/O ) dcvice that functions as a window

into a computer located somewhere else.

An intelligent term inal can perform some

processing operations, but it usually does

not have any storage. In some mainframe

environments, however, workers can use a

standard personal computer to access the

mainframe.

Mainfram es are large, powerful sys­

tems (sec Figure 1A.20). The largest main­

frames can handle the processing needs of thousands of users at any given

moment. But what these systems offer in power, they lack in flexibility. Most

mainframe systems are designed to handle only a specific set of tasks. In your

state's Department of M otor Vehicles, for example, a mainframe system is prob­

ably devoted to storing information about drivers, vehicles, and driver's licenses,

but little or nothing else. By lim iting the number of tasks the system must per­

form , administrators preserve

as much power as possible for

required operations.

You may have interacted p *

with a mainframe system with- A

out even knowing it. For exam- >

pie, if you have o ’er visited an .

airline’s Web site to reserve a H

scat on a flight, you probably JW

conducted a transaction with a |L

mainframe computer.

Introducing Computer Systems 9

FIG U R E 1A.19
Hundreds,eventhousands,of mainframe
usersmayuseterminatetowork*fth ttw
catfralcomputer.

FIG U RE 1A.20
Mainframecomputersare often housed
alone in specialrooms,awayfromM ir
users.

N or& fl.iN E Minicomputers

Formoreinformatonon First released in the 1960s, minicomputers got their name because of their small
mnicompjters, wsrt size compared to other computers of the day. The capabilities of a minicomputer
http://www.mhte.com/ are somewhere between those of mainframes and personal computers. For this
reason, minicomputers are often called midrange computers.

petemorton. Like mainframes, minicomputers can

handle much more input and output

SELF-CHECK :: than personal computers can. Although
some ‘‘minis’’ arc designed for a single

Circle the correctanswer foreach question. user, the most powerful minicomputers

1. Anycomputeris controlledby_____________ can serve the input and output needs of
hundreds of users at a time. Users can
a. hardware b. information c. instructions access a central minicomputer through a

2. Whichofthese is a powerfultypeof personalcomputer,favored byprofessionals terminal or a standard PC.

suchas engineers?

a. workstation b. notebook c. mainframe Supercomputers

3. Whichtypeofcomputerwaiyou mostlikelyencounterat theDepartmentof Motor Supercomputers arc the most powerful
Vehicles? computers made, and physically they
are some of the largest (see Figure
a. smartphone b. mainframe c. supercomputer I A .21). These systems can process huge

10 Chapter 1

Urheberrechllich oeschQtztes Mat

amounts of data, and the fastest super* FIGURE 1A.21
computers can perform more than one
trillio n calculations per sccond. Some Supercomputersare mostcommonin
supercomputers can house thousands unruersltyandresearchsettsigs.buta
of processors. Supercomputers are lew government agencies and very large
ideal for handling large and highly businessesusethemas M l.
complex problems that require ex­
treme calculating power. For example, ONLINE
supercomputers have long been used in
the mapping of the human genome, Formore Mormabonon
forecasting weather, and modeling siperconputers. visit
complex processes like nuclear fission. http://www.mhhc.com/
petemorion.
Computers in Society
FIGURE 1A^ 2 [I:
How important are computers to our society? People often talk in fantastic terms
about computers and their impact on our lives. You probably have heard or read Att?iebognnrg oftho20tnccniry te.v
expressions such as “ computers have changed our world** or “ computers have couldenvisionhowthealterable woiid
changed the way we do everything” many times. Such statements may strike you changeB» world.Today,thosamehctds
as exaggerations, and sometimes they are. But if you stop and really think about true (excomputersandother formsol
the effect computers have had on our daily lives, you still may be astonished. technology.

One way to gauge the impact of computers is to consider the impact of other
inventions. Can you imagine, for instance, the many ways in which American life
changed after the introduction of the automobile (see Figure 1A.22)? Consider a
few examples:

» Because of the cat; people were able to travel farther and cheaper than ever
before, and this created huge opportunities for businesses to meet the needs
o f the traveling public.

» Because vehicles could be mass-produced, the nature o f manufacturing and
industry changed and throngs of people began working on assembly lines.

» Because of road development, suburbs became a feasible way for people to
live dose to a d ty without actually living in one.

» Because of car travel, motels, restaurants, and shopping centers sprang up in
piaccs where there had previously been nothing-

Introducing ComputerSystems 11

Productivity Tip

C hoosin g th e Right Too I fo r the Jo b

Buying a computer is a lot like buying a car because there » Send Faxes and E-Mall. Most popular handheld PCs have
are so many models and options from which to choose! Be­ fox and e-mail capabilities and a port that lets them ex­
fore deciding which model is best for you, identify the type change data with a PC.
of work for which you want to use the computer.
If your job requires you to travel but you still need a full-
Depending on yourjob, you may need to use a computer featured computer, you may consider using a laptop or
on a limited basis. A handheld system is great if you wantto notebook computer. This option is the best choice if you
want to
» Manage Your Schedule on a Daily or Hourly Basis.
Handheld computers are popular for their calendar and » Carry Your Data with You. If you need to make presen­
schedule-management capabilities, which enable you to tations on the road or keep up with daily work while
set appointments, track projects, and record special traveling, portable PCs are ideal laptop systems offer as
events. much RAM and storage capacity as desktop models. Many
portables have built-in CD-ROMor DVD drives; others ac­
» Manage a List of Contacts. If you need to stay in touch cept plug-in CD-ROM, DVD, and hard drives, which can
with many people and travel frequently, personal digital greatly increase their capacity.
assistants provide contact-management features.
» Be Able to Work Anywhere. Portable PCs run on either
» Make Notes on the Fly. Some PDAs feature small key' rechargeable batteries or standard current
boards, which are handy for tapping out quick notes.
Others feature pens, which enable the userto 'w rite" di­ » Communicate and Share Data from Any Location. Most
rectly on the display screen. Many newer handheld sys* portable computers have built-in modems or slots for
terns also provide a built-in microphone, so you can plugging in a modem.
record notes digitally.

Think of other great inventions and discoveries, such as electricity, the telephone,
or (he airplane. Each, in its own way, brought significant changes to the w orld,
and to the ways people lived and spent their time. Today, still relatively soon af­
ter its creation, the computer is only beginning to make its mark on society.

Why Are Computers So Important?

People can list countless reasons for the importance of computers {see Figure
1A.23). For someone with a disability, for example, a computer may offer free­
dom to communicate, learn, or work without leaving home. For a sales profes­
sional, a PC may mean the ability to communicate whenever ncccssary, to track
leads, and to manage an ever-changing schedule. For a researcher, a computer
may be the workhorse that docs painstaking and time-consuming calculations.

But if you took a ll the benefits that people derive from computers, mixed them
together, and distilled them down into a single element, what would you have?
The answer is simple: inform ation.

Computers arc important because information is so essential to our lives. And
information is more than the stuff you see and hear on television. Facts in a text­
book or an encyclopedia are inform ation, bur only one kind. Mathematical for­
mulas and their results arc information, too, as arc the plans for a building or the
recipe for a cake. Pictures, songs, addresses, games, menus, shopping lists, re­
sumes—the list goes on and on. A ll these things and many others can be thought of
as information, and they can a ll be stored and processed by computers. (Actually,

12 Chapter 1

If you work in one place and need to perform various tasks,
a desktop computer is the best choice. Choose a desktop
computer if you want to

» Work with Graphics-Intensive or Desktop Publishing
Applications. Complex graphics and page-layout pro­
grams require a great deal of system resources, and a
desktop system’s large monitor reduces eye fatigue.

» Design or Use Multimedia Products. Even though many
portable computers have multimedia features, you can
get the most for your money with a desktop system.
Large screens make multimedia programs easier to see,
and stereo-style speakers optimize sound quality.

» Set Up Complex Hardware Configurations. A desktop I I Portable carputcn enabteyoutoworkaJmoslanywhere.
computer can support m ultiple peripherals—including
printers, sound and video sources, and various external
devices—at the same time. If you want to swap compo­
nents, or perform other configuration tasks, a desktop
system wiU provide many options.

FIG U RE 1A.23

Tfwbenefitofusingcompilers areas
variedas toe peoptewhouse(hem.

computers store these things as data, not as inform ation, but you’ll learn the dif­
ference between the two later in thb book.) So, when you consider the importance
of computers in our society, think instead about the importance of inform ation. As
tools for working w ith inform ation, and for creating new inform ation, computers
may be one o f humanity's most important creations.

Introducing Computer Systems 13

Jrheberrechllich geschOtetes Ma

: : FIQURE 1A.24 lic p . §•* af p» tm VW M p i D M T o il VMa
m* -laiKl
E-mail softwareandInternetconnections
makeit essy torpeopletokeepin touch.

D a»• « £> * * • ■'.]Q

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d b l K t e f n l r M i l l i M O d 2SI Planta b o q id en |

d rjaMfric wn lVilipM Sxt ei erfm a t ll ifr ii i n
ibM in yea T l a k x ^i
*. m4 ctcl wata

tm , :__________ I J

il____~

INE Home

Formorertormabonon In many American homes, the fam ily computer is nearly as important as the refrig­
computersin mehome,vis# erator or the washing machine. People cannot imagine living without it. In fact, a
http://www.mhhe.com/ growing number of families have multiple PCs in their homes; in most cases, at
petemorton least one of those computers has an Internet connection. W hy do home users need
their computers?
14 Chapter 1
\ » Communications. Electronic m ail (e-mail) continues to be the most popular
use for home computers, because it allows fam ily members to communicate
w ith one another and to stay in contact w ith friends and coworkers (see Fig­
ure 1A.24).

» Business W ork Done at Home. Thanks to computers and Internet connec­
tions, more people arc working from home than ever before. It is possible for
many users to connect to their employer’s network from home and do work
that could not be done during regular business hours. Computers also are
making it easier for people to start their own home-based businesses.

» Schoolwork. Today’s students are increasingly reliant on computers, and not
just as a replacement for typewriters. The Internet is replacing printed books
as a reference tool (see Figure 1A.25), and easy-to-use software makes it
possible for even young users to create polished documents.

» Entertainment. If you haw ever played a computer game, you know how en­
joyable they can be. For this reason, the computer has replaced the television
as the entertainment medium of choice for many people. As computet; audio,
video, and broadcast technologies converge, the computer w ill someday be
an essential component o f any home entertainment center.

» Financcs.'Computcrs and personal finance software can make balancing
your checkbook an enjoyable.experience. W ell, almost. At any rate, they cer­
tainly make it easier, and home users rely on their PCs for b ill paying, shop­
ping, investing, and other financial chores (see Figure 1A.26).

Urheberrechllich geschutzles Material

FIGURE 1A.25

TheInternetis atremendousresourceter
study:offeringthousandsofauthoritative
tttobsiteswherestudentscan find
informationandhdpona l kindsof
subjects.

MH- oliamCa$»r1rd0001t^0t FIG URE 1A.26
Manybanksnowoffertheirservices
Personal banking online.Nyou havean accountwith suft
a bank,youcan accessyouraccounts,
M C C fl.va tfirA ;o t k* ta i* M bat* m tj> i t\* w aj ftu km .89 paybins,andconductothertransactions
online.
corwiam ii'l ■ M htr yM>» on Kw |0 <ryoe |««Ik M tlh a yaw t(n ».«• h M
»»*B—uH■lmm 1I N m lg fc
Oh h a n ld p vtu d t H )n c n («■ n— 4 1*kmk k iM y |w m t. INE

•NajaaMrt Formoreinformationon
computersIn education,vist
D apoalt Sarvicas Loans and Credit httpV/www.mhhe.com/
petemorton
* Oettntfittadi

* Swap *«>J * tiertSnitileeijal
lAtU
(ffttffilSt

9 ctlkafnjl

Education

M ore and more schools are adding computer technology to their curricula, not
only teaching pure computer skills, but incorporating those skills into other
classes. Students may be required to use a drawing program, for example, to draw
a plan of the Alamo for a history class, or use spreadsheet software to analyze
voter turnouts during the last century’s presidential elections.

Educators see computer technology as an essential learning requirement for all
students, starting as early as preschool. Even now, basic computing skills such as
keyboarding are being taught in elementary school dasscs (see Figure 1A.27). In
the near future, high school graduates w ill enter college not only with a general
diploma, but w ith a certification that proves their skills in some area of comput­
ing, such as networking or programming.

Small Business IN E

M any of today’s successful small companies simply could not exist without com­ For moreinformation on
puter technology. Each year, hundreds o f thousands of individuals launch busi­ computersin smaflbusiness,visit
nesses based from their homes or in small-office locations.They rely on inexpensive http://www.mhhe.com/
computers and software not only to perform basic work functions, but to manage petemorton.
and grow their companies.

Introducing Computer Systems 15

INE These tools enable business owners to
handle tasks—such as daily accounting
Formoremtormaiionon chores, inventory management, marketing,
computersin industry,wsit
http://www.mhhe.com/ payroll, and many others—that once re*
pctemorton quired the hiring of outside specialists (see
Figure 1A.28). As a result, small businesses

bccome more self-sufficient and reduce their
operating expenses.

FIG U RE 1A.27 Industry

Basiccomputerskilsare nowbeing Today, enterprises use different kinds of
taughttoearlylearners,whoquicklypick computers in many combinations. A corpo­
upmouseandkeyboarduse. rate headquarters may have a standard
PC-based network, for example, but its
production facilities may use computer*
controlled robotics to manufacture products.

Here arc just a few ways computers are
applied to industry:

» Design. Nearly any company that designs and makes products can use a
computer-aided design or computer-aided manufacturing system in their
creation (sec Figure 1A.29).

» Shipping. Freight companies need computers to manage the thousands of
ships, planes, trains, and trucks that are moving goods at any given moment.
In addition to tracking vehicle locations and contents, computers can manage
maintenance, driver schedules, invoices and billing, and many other activities.

» Proccss Control. Modem assembly lines can be massive, complex systems,
and a breakdown at one point can cause chaos throughout a company. So*
phisricatcd proccss-control systems can oversee output, check the speed at
which a machine runs, manage conveyance systems, and look at parts inven­
tories, with very little human interaction.

H i M V * * l i « i CWNH» CM— I VmWB Cn f c i w litftng W— * H«fr

f l 4 fc W* ? fi> 1 I^
Irmaa* CtfA fen M m I i V«ni OmA M flag Ago* Herd Fad

FIG U RE 1A.28

Easy-lo useaccountingprogramssuch
as OuickBooks allow businessowners to
managetheirfinances,even i!theydo
net have anyaccounting opcrtisa

16 Chapter l

Urheberrechtlich geschutzies Ma

Government FIG U RE 1A.29
Compuier-aideddesignprogramsatow
N ot only are governments big consumers o f technology, but engneersto designandtestnew
they help to develop it as w ell. As you w ill Icam in Chapter 8, producs.andeven tocontrol the
“ Presenting the Internet," the U .S. government played a key machinesthat mamiaduc them.
role in developing the Internet. Sim ilarly, NASA has been in*
volved in the development o f computer technologies of all FormoreInformationon
sorts. Today, computers play a crucial part in nearly every computersingovernment,visit
government agency: http://www.mhhe.com/
petemorton
» Population. The U.S. Census Bureau was one of the first
organizations to use computer technology, recruiting me*
chanical computers known as “ difference engines" to
assist in tallying the American population in the early
20th century.

Taxes. Can you imagine trying to calculate Americans’ tax
bills without the help of computers? Neither could the Internal Revenue
Service. In fact, the IR S now encourages taxpayers to file their tax returns
online, via the Internet.

» M ilitary. Some of the world's most sophisticated computer technology has
been developed prim arily for use by the m ilitary. In fact, some of the earliest
digital computers were created for such purposes as calculating the trajectory
of missiles. Today, from payroll management to weapons control, the armed
forces use the widest array of computer hardware and software imaginable.

Police. When it comes to stocking their crime-fighting arsenals, many police
forces consider computers to be just as important as guns and ammunition
(see Figure 1A.30). Today’s police cruisers are equipped with laptop com*
puters and wireless Internet connections that enable officers to search for
inform ation on crim inals, crime scenes, procedures, and other kinds of
inform ation.

FIG URE 1A.30

Portablecomputersare nowamong
poOcoofficers' weaponsofchoice.

Introducing Computer Systems 17

Urheberrechlllch geschutztes Me £

- 'ffi

The Merging of I V I c d i M c M ^ i M y

I imagine that you have been aware of personal computers first five years of the PCs exis­
for some time. Even if you or your family has never owned a tence, the greatest innovations came from within the world
PC—and even if this course is your first opportunity to use of computing—people researching specifically to improve
one—you're probably at least peripherally aware of the video performance, to reduce the costofincreasingly massive
prominent place we've given to PCs in our lives. Asa matter data storage, to connect computers together over world-
of fact it's only been overthe course ofour lives, yours and shrinking distances. The creativity of these folks was stag­
mine, that PCs have earned their place on desks in homes gering. When faced with the question, " I can talk around the
and places of business, if earned is the right word. Personal world on the telephone; why cant my computer?" for exam­
computers' slow start has accelerated to a staggering pace ple, they literally gave the computer a voice. That's what a
as we humans have done what we always do: Take a new modem does: it turns a computer's digital signals into audi­
tool and exploit its every possible use. ble sound that the plain old telephone system can handle. If
you like, you can think ofthis as being somewhat analogous
For many of us, the 30-year evolution of uses for the PC to the early years of electricity when pioneers such as
has been no less revolutionary than was the introduction of Thomas Edison and George Westinghouse worked tirelessly to
electricity to the homea century ago. What began as a sim­ improve the potential of their original innovation and make
ple, if seemingly miraculous, light to read by has become an arguably honest buck. Other industries—automotive; elec­
the center of most everything we do at home. Why even tronics, and entertainment, to name a prominent few -
many fireplaces—yesterday's reading light—ignite today by adopted the technology developed for and made
electric power. Personal computers started life similarly, as economically feasible by computing's growing popularity
humble things, miraculous for their multipurpose ability to
work with words and numbers, yet able to display virtually Gradually, this relationship became more symbiotic and
nothing but text in response to typed commands, barely the PC started to benefit from technology originally devel­
able to print anything usefully, and closed—unable to com­ oped for other purposes. Consider the compact disc Intro­
municate "outside of the box," as it were. duced in 1980, by 1983 it was just beginning to gain a
foothold in the music world. Six years later, CD-ROMs
A huge industry developed to support personalcomputers appeared on personal computers and ushered in a second
and expand their potential use as a tool And for roughly the

Nnrto Health Care

W c INE Paya visit to your family doctor or the local hospital, and you'll find yourself sur­
rounded by computerized equipment of all kinds. Computers, in fact, arc making
Formominformationon health care more efficient and accurate while helping providers bring down costs.
computers in heaBicare, visa Many different health care procedures now involve computers, from ultrasound
http://Wwwjnhhe.coni/ and magnetic resonance imaging, to laser eye surgery and fetal monitoring (see
petemorton Figure 1A.31).

Surgeons now can use robotic surgical devices to perform delicate operations,
and even to conduct surgeries remotely. New virtual-reality technologies are be­
ing used to train new surgeons in cutting-edge techniques, without cutting an ac­

tual patient.
But not all medical computers arc so high*tcch. Clinics and hospitals use stan­

dard computers to manage schedules, maintain patient records, and perform
billings. Many transactions between physicians, insurance companies, and phar­
macies are conducted by computers, saving health care workers time to devote to
more important tasks.

18 Chapter 1

generation of PC possibilities. PCs by then had evolved so­ profit the computing world turned back to substance with
a renewed focus on the PCas the center of media. As I write
phisticated graphical user interfaces and detailed displays. this, a new generation of media PCs is appearing on the
market. These systems can blend virtually every media tech­
Combining the CD's digital sound with these visual tech­ nology in existence into a seamless, single experience. The
nologies went a long way toward making computer experi­ traditional capabilities of PCs, CD and DVD players, DVD
recorders, televisions, VCRs, surround-sound music systems
ences interactive—something that previously only people can all be provided by one device— or two, if you add the
possibilities of printing and film . What's really new about
and unpopulartoys had been. The PC world increasingly be­ these systems is their power—practical video editing has
been the private world of a wealthy few until the latest ad­
came a place where many other worlds met particularly the vances in processor, memoiy, and massive storage a ll came
together in affordable systems that put these capabilities
varied worlds of information and entertainment—an inter­ into homes and small offices.
active, multimedia world.
This means that you can produce your own DVD movies
This is today's world. It's a world in which we expect our with just a consumer video camera and a media PC (fast-
talking agents are now entirely optional). In a band? Record
to toot, whistle, plunk, and boom; to speak to us and distribute albums of your music directly or through a
an to listen when we dictate; to rememberwhat we forget Web site that software almost automatically designs foryou.
Paint? Create your own online gallery. Write? Self-publish on
^ iat_t*,S*Tac* us so we w ill forget. Having spent much of demand while promoting your creations through an existing
onUne bookseller. Watt Disney said, “If you can dream it you
actuall* ^getting that a technology company must can do it* Technology has helped prove him right Todaythe
"you" who can “do it” means more people from more cultures
y produce something useful in order to realize a and backgrounds than ever before.

FIGURE 1A.31

Computersmakemanyhealthcare
proceduresmoreaccurateandmore
comfortableforpalenls.

Introducing ComputerSystems 19

Summary Review

Chapter 1 » A computer is an electronic device that processes data, converting it into informa­
tion that is useful to people.

» There are two basic types of computers: analog and digital. The computers com­
monly used today are all digital computers.

» Computers can be categorized by the number of people who can use them simulta­
neously, by their power, or by other criteria.

» Computers designed for use by a single person include desktop computers, work­
stations, notebook computers, tablet computers, handheld computers, and smart
phones.

» The terms personal computer (PC) and microcomputer can be used when referring
to any computer meant for use by a single person.

» The desktop computer is the most common type of personal computer. This com­
puter is designed to sit on top of a desk or table, and comes in two basic styles.

» A workstation is a specialized, single-user computer that typically has more power
and features than a standard desktop PC.

» Notebook computers are full-featured PCs that can easily be carried around.
» A tablet PC is another type of portable PC, but it can accept handwritten input

when the user touches the screen with a special pen.
» Handheld personalcomputers are computing devices that fit in your hand; the per­

sonal digital assistant (POA) is an example of a handheld computer.
» Smart phones are digital cellular phones that have features found in personal com­

puters, such as Web browsers, e-mail capability, and more.
» Some types of computers—such as network servers, mainframes, minicomputers,

and supercomputers—are commonly used by organizations and support the com­
puting needs of many users.
» A network server is a powerful personal computer that is used as the central com­
puter in an organization's network.
» Mainframes are powerful special-purpose computers that can support the needs of
hundreds or thousands of users.
» Minicomputers support dozens or hundreds of users at one time.
» Supercomputers are the largest and most powerful computers made.
» Many families have at least one computer and an Internet connection in their
home and use their PC for tasks such as communication, work, schoolwoik, and per­
sonal finances.
» Computer technology is playing an ever-growing role in schools, where students are
being taught computer skills at younger ages and asked to incorporate computers
into their daily work assignments.
» Computers enable small businesses to operate more efficiently by allowing workers
to do a wider variety of tasks.
» In industries of all kinds, computers play vital roles in everything from personnel
management, to product design and manufacturing, to shipping.
» Governments not only use a great dealof computer technology, but also contribute
to its development.
» Computers ate involved in nearly every aspect of the health care field, from man­
aging schedules and handling billing, to making patient diagnoses and performing
complex surgery.

iberrechtlich geschutztes

Review

Key Terms :: microcomputer, 5 smart phone, 8
midrange computer, 10 stylus, 7
computer, 4 minicomputer, 10 supercomputer, 10
desktop computer, 5 mobile computer, 7 system unit 6
digital pen, 7 network server, 8 tablet PC, 7
docking station, 7 notebook computer, 6 terminal, 9
handheld personalcomputer, 7 workstation, 6
input/output (I/O) device, 9 personalcomputer (PC), 5
laptop computer, 6 personaldigital assistant (PDA), 7
mainframe, 9

Key Term Quiz ::

Complete each statement by writing one of the terms listed under Key Terms in each blank.
1. The______________ is the case that holds the computers critical components.
2. A (n )______________ is a specialized, single-user computer that typically has more power than a standard PC.
3. When not in use, a(n )______________ computer folds up for easy storage.
4. A tablet PC lets you use a (n )______________ to tap or write directly on the screen.
5. A popular type of handheld computer is the______________ _
6. A (n)______________ is usually a powerful personal computer that functions as the primaiy computer in a
network.
7. In a traditional mainframe environment each user accesses the mainframe through a device called a(n)

8. A terminal is an example of a(n )______________ device.
9. The capabilities of a(n )_____________ _ are somewhere between mainframes and personal computers.
10. ______________ are the mostpowerful computers made.

Introducing Computer Systems 21

Urheberrechllich geschulztes Material

Multiple C h o ic e ::

Circle the word or phrase that best completes each statement.

1. A computer converts data into this.

a. information b. charts c . software d. input/output

2. The earliest computers were_________ .systems.
c. analog
a. digital b. paper d. slide rule

3. Mostcomputers are meantto be used by only one _ . at a time.
c. organization
a. company b. program d. person

4. Personalcomputers are also called_______________

a. minicomputers b. microcomputers c. maxicomputers d. supercomputers

5. Many scientists, engineers, and animators use specialized computers, called _

a. personal digital b. minicomputers c. workstations d. networks
assistants

slN I 6. Notebook PCs fall into a category of devices called______________ _

a. mobile computers b. small computers c. handheld computers d. minicomputers

7. Some notebook systems can be plugged into one of these devices, which give the computer additional features,

a. port station b. network station c . workstation d. docking station

8. Some tablet PCscan be connected to a keyboard and a full-size______________ _

a. computer b. monitor c. PDA d. workstation

9. Network servers are sometimes set up in groups that may be called______________ or server forms.

a. units b. workgroups c . clusters d. racks

10. A (n )______________ terminal can perform some processing operations.

a. system b. input/output c. computing d. intelligent

22 Chapter 1

Urheberrechtlich geschutzles Material

LESSO N //m

Review Questions ::

In your own words, briefly answer the following questions.

1. What is a computer?
2. Explain a few of the different ways in which computers can be categorized.
3. List six types of computers that are designed for use by a single person.
4. Describe the two common designs for desktop computers.
5. How much do notebook computers typically weigh?
6. List four types of computers that are designed for use by organizations, and are commonly used by multiple people

at the same time.
7. Why are mainframe systems usually limited in the number of tasks they perform?
8. What is the most popular use for home computers?
9. How are computer technologies used by the military?
10. How are computer technologies being used to train surgeons?

Lesson L a b s ::

Complete the following exercises as directed by your instructor.
1. During the course of a normalday, keep a list of your encounters with computers of various kinds. Your list should

show the place and time of the encounter, the type of interaction you had with the technology, and the results of
that interaction. (Remember, computers can take many sizes and forms, so be alert to more than just PCs.) Share
your list with the class.
2. -Paya visit to any business or government office in your town, and observe the people working there. Are they using
computers? Simply by watching, can you tell whatkinds of computers they are using and what types of work they are
performing? In a single paragraph, list your findings and explain the reasoning behind them. Be prepared to share
your findings with the dass.

Introducing Computer Systems 23

Looking Inside O v e rv ie w : D is s e c tin g th e U ltim a te M a ch in e
the Computer
System Most people believe that computers must be extremely complicated de­
vices, because they perform such amazing tasks. To an extent, this is
O BJECTIVES:: true. As you w ill learn later in this book, the closer you look at a com*
-> List the four parts of a complete puter’s operation, the more complex the system becomes.

computer system. But like any machine, a computer is a collection of parts, which are
> Name the four phases of the categorized according to the kinds of work they do. Although there are
many, many variations on the parts themselves, there are only a few ma­
information processing cycle. jor categories. 1/ you learn about those fam ilies of computer compo­
» Identify four categories of nents and their basic functions, you w ill have mastered some of the
most im portant concepts in computing. As you w ill see, the concepts
computer haidware. are simple and easy to understand.
> List four units of measure for
This lesson gives you a glimpse inside a standard desktop computer
computer memory and storage. and introduces you to its most im portant parts. You w ill learn how
> Name the two most common these components work together and allow you to interact with the sys­
tem. You also w ill discover the importance of software, without which
input and output devices. a computer could do nothing. Finally, you w ill see that the user is (in
Name and differentiate the two mostcases, at least) an essential part of a complete computer system.
main categories of storage
devices.
» Name and differentiate the two
main categories of computer
software.
» Explain the difference between
data, information, and programs.
> Describe the role of the user,
when working with a personal
computer.

A completecompute*system.

The Parts of a Computer System

As you saw in Lesson 1A, computers come in many varieties, from the tiny com*
puters built into household appliances, to the astounding supercomputers that
have helped scientists map the human genome. But no matter how big it is or how
it is used, every computer is part of a system. A complete computer system con­
sists of four parts (see Figure IB .1 ):

» Hardware

» Software
» Data
» User

Hardware

The mechanical devices that make up the computer are called hardware. Hard*
ware is any part of the computer you can touch (see Figure 1B.2). A computer’s
hardware consists of interconnected electronic devices that you can use to control
the computer’s operation, input, and output. (The generic term device refers to
any piece of hardware.)

Software

Software is a set of instructions that makes the computer perform tasks. In other
words, software tells the computer what to do. (The term program refers to any
piece of software.) Some programs exist prim arily for the computer's use to help
ir perform tasks and manage its own resources. Other types of programs exist for
the user, enabling him or her to perform tasks such as creating documents. Thou­
sands of different software programs arc available for use on personal computers
(see Figure 1B.3).

Data FIG U RE 1B.2

Data consist of individual facts or pieces of information that by themselves may WhetfwrIt's a keyboard,aprinter,ora
not make much sense to a person. A computer’s prim ary job is to process these PDA,If youcan touchR.it is hardware.
tiny pieces of data in various ways, converting them into useful inform ation. For

Introducing Computer Systems 25

Urheberrech

FIG U RE IB .3 example, if you saw the average highway mileages of six
different cars, a ll the different pieces o f data might not
Avisit toanysoftwarestorerevealsa mean much to you. However; if someone created a chart
(toying varietyofproducts. from the data that visually compared and ranked the ve­
hicles’ mileages, you could probably make sense of it at a
Norton glance (see Figure 1B.4). This is one example of data be­
ing processed into useful inform ation.
ONLINE
Users
For moreinformationon tfio
informationprocessing cyda,visit People are the computer operators, also known as users.
http^AvwvunhhexMn/ It can be argued that some computer systems are com­
petemorton. plete without a person’s involvement; however, no com­
puter is totally autonomous. Even if a computer can do its
job without a person sitting in front of it, people still design, build, program, and
repair computer systems. This lack of autonomy is especially true of personal
computer systems, which arc the focus of this book and are designed specifically
for use by people.

The Information Processing Cycle

Using a ll its parts together, a computer converts data into inform ation by per­
forming various actions on the data. For example, a computer might perform a
mathematical operation on two numbers, then display the result. O r the computer
might perform a logical operation such as comparing two numbers, then display
that result. These operations are part of a process called the inform ation process*
ing cycle, which is a set of steps the computer follows to receive data, process the
data according to instructions from a program, display the resulting information
to the user, and store the results (see Figure IB-5).

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3 B ? x a* e* - - •r. * s - t u i I I 3.

¥ u - ■ / it B a s i l ] • * » 'A ft » a t
ifll” • * _________

A I B- j.1

t H ighw cy M l« « o « C o m o v ito n t

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3 C«r Mlto«o> H ighw ay M ileage C o m p a riso n s

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FIG URE 1B.4 iMHeaoe 23.7 19.1 15.4 125.5 12.2 27.8
ConvertingpiecesoldataWo useful
Informatione a toytaskd computers. *»~«Jl0mlZ9SKr .11*

26 Chapter 1

FKH IRB IB .5
Theiniorroadonprocessingcyde.

The information processing cycle has four parts, and each part involves one or
more specific components of the computer:

» Input. During this part of the cycle, the computer accepts data from some
source, such as the user or a program, for processing.

» Processing. During this part of the cycle, the computer’s processing compo­
nents perform actions on the data, based on instructions from the user or a
program.

» Output. Here, the computer may be required to display the results of its pro­
cessing. For example, the results may appear as text, numbers, or a graphic
on the computer’s screen or as sounds from its speaker. The computer also
can send output to a printer or transfer the output to another computer
through a network or the Internet. Output is an optional step in the informa­
tion processing cycle but may be ordered by the user or program.

» Storage. In this step, the computer permanently stores the results of its pro­
cessing on a disk, tape, or some other kind of storage medium. As with out­
put, storage is optional and may not always be required by the user or
program.

Essential Computer Hardware

A computer’s hardware deviccs fall into one of four categories (see Figure 1B.6):

1. Processor
2. Memory
3. Input and output
4. Storage

While any type of computer system contains these four types of hardware, this
book focuses on them as they relate to the personal computet; or PC.

Introducing ComputerSystems 27

Jrh

FIG U R E 1B.6
Typesofhardwaredwtces

Processing Devices

The procedure that transform s raw data into useful inform ation is called process­

f or rrofo nttm aton on ing. To perform this transform ation, the com puter uses tw o components: the
computer processors, visit
http://vrww.nihhc.com/ processor and memory.
petemorton.
The processor is like the brain of the com puter; it organizes and carries out in ­
FIG U R E 1B.7
Processing devices. structions that come from either the user or the software. In a personal computet;

FIG U R E 1B.B the processor usually consists o f one or more special­
Early PC rreaocrocessors were not much
larger lhan a numtmail. Processors such ized chips, called microprocessors, which are slivers of
8$ Intel's Pentium 4 are considerably
larger. silicon or other m aterial etched w ith many tin y elec­
28 Chapter 1
tronic circuits. To process data or com plete an instruc­

tion from a user or a program , the com puter passes

Motherboard electricity through the circuits.

As shown in Figure IB .7 , the microprocessor is

QlCUltoanl plugged into the computer’s motherboard. The mother-
board is a rigid rectangular card containing the cir­

cuitry that connects the processor to the other

hardware. The motherboard is an example o f a circuit

Themicroprocessor board. In most personal computers, many internal de­
ls Inside tftls case. vjccs— suc^ as video cards, sound cards, disk con­

trollers, and other devices— are housed on their own
sm aller circuit boards, which attach to the mother­
board. In many newer computers, these devices are
built directly into the motherboard. Some newer m i­
croprocessors are large and complcx enough to require
their own dedicated circuit boards, which plug into a special slot in the mother­
board. You can think of the motherboard as the master circuit board in a com­
puter.
A personal computer’s processor is usually a single chip or a set o f chips con­
tained on a circuit board. In some powerful computers, the processor consists of
many chips and the circuit boards on which they arc mounted. In ei­
ther case, the term ccntral processing unit (C PU ) refers

to a computer’s processor (sec Figure 1B.8). Peo­
ple often refer to computer systems by the
type o f CPU. they contain. A "Pentium 4”

system, for example, uses a Pentium 4 m icro­
processor as its CPU.

Urheberrechtl

Memory Devices Formoreinformationon
computermemory,vtefl
In a computer, memory is one or more sets of chips that store data and/or pro* http7Anrwwjnhhe.com/
gram instructions, cither temporarily or permanently. Memory is a critical pro* petemorton
cessing component in any computer Personal computers use several different
types of memory, but the two most important arc called random access memory
(RAM) and read-only memory (ROM). These two typesof memory work in very
different ways and perform distinct functions.

Random Access Memory

The most common type of memory is called random access memory (RAM). As a

result, the term memory is typically used to mean RAM. RAM is like an elec­

tronic scratch pad inside the computer. RAM holds data and program instruc­

tions while the CPU works with them. When a program is laundied, it is loaded

into and run from memory. As the program needs data, it is loaded into memory

for fast acccss. As new data is entered into the computer, it is also stored in mem­

ory—but only temporarily. Data is both written to and read from this memory.

(Because of this, RAM is also sometimescalled read/write memory.)

Like many computer components, RAM is made up of a set of

chips mounted on a small circuit board (see Figure 1B.9).

RAM is volatile, meaning that it loses its contents when the

computer is shut off or if there is a power failure. Therefore,

RAM needs a constant supply of power to hold its data. For this

reason, you should save your data files to a storage device fre­

quently, to avoid losing them in a power failure. (You will learn more

about storage later in this chapter.)

RAM has a tremendous impact on the speed and power of a computer. Random access memory (RAM).
Generally, the more RAM a computer has, the mote it can do and the faster it can

perform certain tasks. The most common measurement unit for describing a com­

puters memory is the byte—the amount of memory it takes to store a single char­

acter such as a letter of the alphabet or a numeral. When referringto a computer's

memory, the numbers are often so large that it is helpful to use terms such as kilo­

byte (KB), megabyte (MB), gigabyte (GB), and terabyte (TB) to describe the values

(seeTable 1B.1).

Today’s personal com­ T A B L E 1B.1
putersgenerally haveat least

256 million bytes (256 MB) Units of Measure for Computer Memory and Storage

of random access memory.

Many newersystems feature U nit Approximate Actual
512 MB or more. Abbreviation Pronounced Value (bytes) Value (bytes)

Read-Only Memory Kilobyte KB KIU.-uh-bite 1.000 1,024
1,048,576
Unlike RAM, tead-only Megabyte MB MEHG-uh-bite 1.000,000 1,073,741,824
memory (ROM) perma­ (1 million) 1,099,511,627,776

nently stores its data, even Gigabyte GB GIG-uh-bite 1.000,000,000
when the computer is shut Terabyte TB TERR-uh-bite (1 billion)
off. ROM is called non­
volatile memory because it 1,000,000,000,000
(1 trillion)
never loses its contents.

ROM holds instructions

that the computer needs to operate. Whenever the computer's power is turned on,

it checks ROM for directions that help it start up, and for information about its

hardware devices.

Introducing ComputerSystems 29

Jrh e b e rre