Computers: Tools for an Information Age

Chapter 1

Objectives

• Describe the three fundamental characteristics of computers

• Describe at least four areas of society in which computers are used

• Identify the basic components of a computer system: input, processing, output, and storage

• List some common input, output, and storage media• Distinguish data from information• Describe the significance of networking• Explain the significance of the Internet• Explain the various classifications of computers

Contents

• Information Age

• Computer Literacy

• Where Computers Are Used

• Computer System

• Network

• Classifications of Computers

• Evolving more rapidly than Industrial Age

• Will continue into the current century

Information Age

Cornerstones of our Economy

• Land

• Labor

• Capital

• Information

Forging a Computer-Based Society:

Jobs

• From physical to mental

• From muscle-power to brain-power

Forging a Computer-Based Society:

A Computer in Your Future• Where used?

– Bank withdrawal– Supermarket– Drive the car

• Do I need a Personal Computer?– Half of Americans have one at home– Many more use at work

• Will I use a computer in my future career?– Almost every job will involve use of a computer

Computer Literacy

• Awareness– Importance– Versatility– Pervasiveness in our society

• Knowledge– What are computers– How do computers work– Terminology

• Interaction– Use some simple computer applications

The Nature of Computers

Characteristics• Speed• Reliability• Storage capability

Results• Productivity• Decision making• Cost reduction

Where Computers Are Used Graphics

Graphs and charts

Animated graphics

Visual walk-through

Where Computers Are UsedEducation

• Teaching and testing aid

• Learning by doing

• Computer-based instruction

Where Computers Are UsedRetailing

• Bar codes for pricing and inventory

• Shipping

Where Computers Are UsedEnergy

• Locate oil, coal, natural gas, and uranium

• Monitor the power network

• Meter reading

Where Computers Are UsedLaw Enforcement

• National fingerprint files

• National files on criminal

• Computer modeling of DNA

Where Computers Are UsedTransportation

• Cars

• Run rapid transit systems

• Load containerships

• Track railroad cars

• Monitor air traffic

Where Computers Are UsedMoney

• Record keeping

• Banking by phone

• Credit cards

Where Computers Are UsedAgriculture

• Billing

• Crop information

• Feed combinations

• Livestock breeding and performance

Where Computers Are UsedGovernment

• Forecast weather

• Manage parks

• Process immigrants

• Social Security benefits

• Taxes

Where Computers Are UsedThe Home

• Educational tool• Record keeping• Letter writing• Budgeting• Drawing and editing

pictures• Newsletters• Connecting with others

Where Computers Are UsedHealth and Medicine

• Monitor patients

• Electronic imaging

• Diagnose illnesses

Where Computers Are UsedRobotics

• Perform jobs that are dangerous for humans

• Factory work

Where Computers Are UsedThe Human Connection

• Assist the disabled

• Assist athletes by monitoring their movements

Where Computers Are Used

The Sciences• Research

• Simulation

Connectivity• Communication

• Telecommuting

Where Computers Are Used

Training• Airline pilots

• Railroad engineers

Paperwork• Junk mail

• Term paper

• Record keeping

Computers are all around!

• Grocery store

• School

• Library

• Bank

• Mail

We interact with computers everyday!We interact with computers everyday!

Computer System

People

Software

Hardware

People

• Computer programmer – person who writes programs

• Users or End-users – make use of the computer’s capabilities

Software

• Programs

• Set of instructions that directs the hardware to do a required task and produce the desired results

HardwareBasic Components of a

Computer

Computer

• A machine that can be programmed to accept data (input), process it into useful information (output), and store it away (in secondary storage device) for safekeeping or later reuse

• Process is directed by software but performed by the hardware

Function of Computer System

Data handling

I Input

P Process

O Output

S Storage

Input devices

• Accept data or commands and convert them to electronic form

• Getting data into the computer

– Typing on a keyboard

– Pointing with a mouse

– Scanning with a wand reader or bar-code reader

– Terminal

Output devices

Monitor or screen• Text• Numbers• Symbols• Art• Photographs• Video

Printer• Black and white• Color

• Convert from electronic form to some other form

• May display the processed results

• Usable information

The Processor

Central Processing Unit (CPU)

• Converts data to useful information

• Interpret and execute instructions

• Communicate with input, output and storage

Two Types of Storage

• Secondary storage

long-term storage

• Primary storage or memory

temporary storage

Memory / Primary Storage

• Temporary storage

• Holds input to be processed

• Holds results of processing

• Contains the programs to control the computer and manipulate input into output

• Volatile

Secondary Storage

• Long-term storage

• Non-volatile

Secondary Storage Examples• Magnetic disks – read and written by

magnetic disk drive– Hard disk– Diskette

• Optical disks – read and written by optical disk drives– CD-ROM– DVD-ROM

• Magnetic tape – read and written by magnetic tape drives– Primarily used for back-up

Computer System

• Computer– CPU– Memory

• Peripheral equipment– Connected to the computer by a cable– Input, output, storage

Network

• Definition– A system that uses communications equipment

to connect computers and their resources.

• Types– Local area network (LAN) – connects computers

in close proximity

– Metropolitan are network (MAN) – connect computers between buildings in the same geographic area

– Wide are network (WAN) – connects computers over great distances

Home Connectivity

• Connect home PC to other computers

• Use modem to convert signals between electronic (computer) and analog (voice) formats

Internet

• Collection of networks• No ownership• No central source for services available• No comprehensive index of what information

is available

Individuals

Businesses

Organizations

Libraries

Research labs

Government

Connects Everyone!

Getting Connected

• User’s computer must connect to a server

• Server must communicate using TCP/IP

• The user can purchase access to a server from an ISP (Internet Service Provider)

Internet – What Can You Do?

• WWW – World Wide Web

• FTP – File Transfer Protocol

• E-mail

• UseNet

• IRC – Internet Relay Chat

• Bulletin Boards

World Wide Web

• Browser – program that allows the user to move around and explore the Internet

• Use the mouse to point and click on text and graphics

• Web page

• Web site

• Home page

Classifications of Computers

• Use the computer that fits your needs

• Based upon– Size– Speed– Cost– Portability– Number of simultaneous users supported– Available software– Typical use

Personal Computers

• Other names– PC– Microcomputer– Home computer

• Categories– Low-end functional– Fully powered– Workstations– Net computer or net box (Web TV)

• Desktop Models

Notebook Computers

• Portable– Lightweight– Fits in a briefcase– Battery operated

• Laptop– Larger– Heavier

• More expensive that desktop models

Handheld Computers

• Personal Digital Assistant (PDA)– Scheduling– Addresses– Handwritten input– May offer wireless e-mail and fax

• Pocket– More power than PDA– Runs basic productivity software

Other Types of Computers

Mainframes– High speed– More expensive– Used to process large amounts of data quickly– Support multiple users– Does server tasks

Supercomputers– Fastest speed– Most expensive