Welcome to CMPE003 Personal Computer Concepts: Hardware and Software

Welcome to CMPE003 Personal Computer Concepts: Hardware and Software

Winter 2003UC Santa Cruz

Instructor: Guy Cox

Computers:Tools for an Information Age

Chapter 1 – Part bComputers: Tools for an Information Age

Forging a Computer-Based Society Traditional Cornerstones of

Economy: Land Labor Capital

New Economic Element: Information

Computers are all around!

Grocery store School Library Bank Mail

We interact with computers everyday!

Fundamental Characteristics

Speed Reliability Storage Capability By-products (or Benefits)

Benefits of Computers

Productivity Workers use computers to do their jobs faster and better Many processes can be more efficiently controlled by

computers Decision Making

Helps decision makers sort out financial, geographical, and logistical factors

Cost Reduction Helps hold down costs of labor, energy and paperwork

Chapter Objectives Describe the three fundamental characteristics of computers

Speed, reliability & storage 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 (IPOS) List some common input, output, and storage media Distinguish raw data from information Describe the significance of computer networks Explain the significance of the Internet Explain the various classifications of computers

Computer System

People

Software

Hardware

People

Hardware Engineers – People who design and build computers

Software Engineers (programmers) – People who design and write software

programs

Users or End-users – People who 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

Hardware – Basic Components of a Computer

What Is a Computer?

A machine that can be programmed to accept data, process it into useful information, and store it away Data: raw facts representing people and events Information: data that is organized, meaningful,

and useful

Functions in a Computer System

What is a computer? Four primary

components: Input devices Processor Output devices Storage

Input: What Goes In

Input: the data or commands put into the computer for processing

Common input devices: Keyboard Mouse Scanner Microphone Camera

Keyboard

Most common input device Generates electrical signals

which are translated into characters

Mouse

Moves over a flat surface Movement of mouse ball causes corresponding

movement of pointer on screen

Scanner

Reads special letters, numbers, and symbols Wand reader, bar code

reader often used in stores

Flatbed and sheet-fed scanners scan pictures or printed documents

The Processor and Memory:Data Manipulation Processor

Also called central processing unit (CPU) Memory (primary storage)

Closely related to, but distinct from processor Provides temporary storage

Primary Storage

Used to temporarily hold data After it is retrieved from input device and before it

is processed After it is processed and before it is released to

output device Temporary (volatile) storage

Data in memory lost if power is lost or program closed

The Processor

Center of activity in the computer Consists of electronic circuits

Interprets and executes program instructions Communicates with input, output, and storage devices

Transforms data into information

Output: What Comes Out

Output: the result produced by the CPU Common forms of output: text, numbers,

graphics, and sounds Common output devices:

Screen (monitor): can display text, numbers, photographs, even video, in full color

Printer: produces printed reports as instructed by a program

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

Speakers MusicCDs, DVDs

Secondary Storage

Provides long-term storage Separate from memory

Common media Magnetic disks Optical disks Magnetic tape

Caveat -- “Bit rot”• Data can be lost or

changed over time

Magnetic Disks

The most common storage media Diskette: 3.5” flexible diskette in plastic case Hard Disk: more storage capacity and faster access

than diskette

Optical Disks

Use a laser beam to read large volumes of data inexpensively CD-ROMs DVD-ROMs

Magnetic Tape

Stores large amounts of data inexpensively Often used for system backup

Peripheral Devices

All hardware devices attached to the computer Includes all input, output, and storage devices

Networking

Network: a system that uses communications equipment to connect computers and their resources

Common network tools: Local Area Network (LAN) Wide Area Network (WAN) Modem Electronic mail

Local Area Network (LAN)

Personal computers in an office are connected so users can communicate Users can operate computers independently Can share resources and exchange data

Wide Area Network (WAN)

Wide area network (WAN) – connects computers over great distances A WAN may connect several LANs

The Internet

The largest and most far-flung network Connects users worldwide Not actually a network, but a collection of

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

is available

Internet

IndividualsBusinessesOrganizations

Libraries Research labsGovernment

ConnectsEveryone!

Electronic Mail (e-mail)

Send and receive messages electronically Can send text, pictures, links to Web sites Can attach files for collaboration

Messages stored in computer “mailbox”

Getting Connected

To access the Internet, connect to a server computer Server receives, processes, and transmits

information Computers use a standard to communicate Need an Internet Service Provider (ISP)

Home Connectivity

Connect home PC to other computers (Usually via an ISP)

Use modem to convert signals between electronic (computer) and analog (voice) formats Dial-up modem ADSL modem Cable modem

Modem

A device that allows users to communicate with other computers over telephone lines Required when you don’t have a digital

connection such as DSL or a cable modem

Internet Service Providers

The owner of a server computer Charges a fee for access to the Internet

Fee can provide unlimited access or be based on usage

Provides the user a means to connect to the server Once connected, you can connect to the Internet

and all other server computers

Computer Protocols

Provides a standard way to communicate with other computers Transmission Control Protocol/Internet Protocol

(TCP/IP) used on the Internet Allows different types of computers to share data

Getting Around the Internet

Began as a means for Department of Defense and its research institutions to share information Information was text-only Commands to navigate were obscure

Now, much more visually based Use browser to explore the Internet World Wide Web

Browser

Software that allows you to use a mouse to explore the Internet Click on screen text and/or graphics to move to

different locations Most commonly used to explore the World Wide Web

The World Wide Web

A subset of the Internet Actually, a standard for

displaying and transmitting information

Web site: a location on the Web Home page: the main

page of a Web site

Classification of Computers

Personal Computers Notebook Computers Handheld Computers Midrange Computers Mainframes Supercomputers

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 Desktop computers

Also known as PCs, microcomputers, or home computers Broken down into three categories:

Low-end computers Fully-powered personal computers Workstations

Network computer Central processing unit and minimal memory Designed to be used on a network

Sometimes called thin client

PC Categories Low-end computers

Fine for home users, word processing, simple games, Internet access

Fully powered computers Good for heavy use of graphics, programming, or action-

oriented games Workstations

Very high-end computers used by engineers, financial traders, and graphic designers

Notebook Computers

Small, lightweight computers Capabilities approach that of

desktop computers Similar processing and memory Most have hard disk, and diskette

or CD-ROM drive Typically more expensive than

comparable desktop computers

Handheld Computers

Personal Digital Assistant (PDA) Keeps track of appointments,

contacts, etc. Accepts input with hand-held stylus

Pocket PC Offers capabilities of PDAs, plus the

ability to run stripped-down versions of software such as word processing and spreadsheets

Other Types of Computers Client/Servers

client processes requesting service from server processes clients and servers running on the appropriate hardware and

software Mainframes

High speed More expensive Used to process large amounts of data quickly

Transaction processing Support multiple users Does server tasks

Supercomputers Fastest speed Most expensive

Midrange Computers

Multi-user computers designed to serve the needs of medium-sized organizations Hundreds or thousands of users connected Used for inventory, order-entry, and other

company-wide applications

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Mainframes

Very large and powerful computers Capable of processing billions of instructions per

second Capable of handling billions of characters of data

Often used for applications with many users Reservations systems Large mail-order houses E-mail servers

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Supercomputers

The fastest and most powerful computers

Capable of processing trillions of instructions per second

Used for very sophisticated applications requiring mammoth data manipulation:

Weather forecasting Weapons research Special effects for movies

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