1Copyright © Prentice Hall 2000 An Overview of Computers Chapter 1 Computer Hardware

2Copyright © Prentice Hall 2000 The Big Picture A computer system contains:A computer system contains: hardware (equipment)hardware (equipment) software (programs)software (programs) people (programmers and end-users)people (programmers and end-users) hardware software people

3Copyright © Prentice Hall 2000 Hardware: The Basic Components of a Computer

4Copyright © Prentice Hall 2000 A computer is a machine that can be programmed to accept dataaccept data process it into useful informationprocess it into useful information store it away for safekeeping and later usestore it away for safekeeping and later use InputProcessing Output Secondary Storage

5Copyright © Prentice Hall 2000 Input Devices Accept external data or commandsAccept external data or commands InputProcessing Output Secondary Storage Send data or commands to the processorSend data or commands to the processor

6Copyright © Prentice Hall 2000 Processing Unit Also known as the Central Processing Unit (CPU)Also known as the Central Processing Unit (CPU) Executes computer instructionsExecutes computer instructions InputProcessing Output Secondary Storage Manipulates input data into information people wantManipulates input data into information people want

7Copyright © Prentice Hall 2000 Output Devices Show people the processed data in understandable terminologyShow people the processed data in understandable terminology InputProcessing Output Secondary Storage

8Copyright © Prentice Hall 2000 Storage Secondary storage devices such as disks store data and programsSecondary storage devices such as disks store data and programs InputProcessing Output Secondary Storage Primary storage (or memory) holds programs and data temporarilyPrimary storage (or memory) holds programs and data temporarily

9Copyright © Prentice Hall 2000 Your Personal Computer Hardware

10Copyright © Prentice Hall 2000 Input: What Goes In Typing on a keyboardTyping on a keyboard Pointing with a mousePointing with a mouse Scanning with a wand reader or bar-code readerScanning with a wand reader or bar-code reader May be part of a terminalMay be part of a terminal

11Copyright © Prentice Hall 2000 The Processor and Memory: Data Manipulation

12Copyright © Prentice Hall 2000 The Processor Consists of circuits that interpret and execute program instructionsConsists of circuits that interpret and execute program instructions Communicates with the input, output, and storage devicesCommunicates with the input, output, and storage devices

13Copyright © Prentice Hall 2000 Data The raw material to be processedThe raw material to be processed When processed, becomes:When processed, becomes: Information - organized, meaningful, and useful dataInformation - organized, meaningful, and useful data Price: $10, Quantity: 5

14Copyright © Prentice Hall 2000 Memory Holds data after input and before processingHolds data after input and before processing Holds data after processing but before release to the output deviceHolds data after processing but before release to the output device Holds programs needed by the CPUHolds programs needed by the CPU memory chip w/package removed

15Copyright © Prentice Hall 2000 Output: What Comes Out Data that has been processed into useful informationData that has been processed into useful information InputProcessing Output Secondary Storage Text, numbers, graphics, sounds from the computer, also film, voice, musicText, numbers, graphics, sounds from the computer, also film, voice, music

16Copyright © Prentice Hall 2000 Secondary Storage Provides storage separate from memoryProvides storage separate from memory Magnetic and optical disksMagnetic and optical disks InputProcessing Output Secondary Storage Magnetic tape - usually cartridge format like a cassetteMagnetic tape - usually cartridge format like a cassette

17Copyright © Prentice Hall 2000 The Complete Hardware System Hardware devices are known as peripheralsHardware devices are known as peripherals –All input, output, and storage devices –May be as close as the same cabinet or as far apart as separate countries

18Copyright © Prentice Hall 2000 Networking Network - a computer system that uses communications equipment to connect computers and their resources.Network - a computer system that uses communications equipment to connect computers and their resources.

19Copyright © Prentice Hall 2000 Networking May involve phone-line connectivity through a modemMay involve phone-line connectivity through a modem Allows for services such as Allows for services such as

20Copyright © Prentice Hall 2000 The Internet Largest and most far-flung network system of them all, connecting users worldwideLargest and most far-flung network system of them all, connecting users worldwide Composed of thousands of loosely organized component networksComposed of thousands of loosely organized component networks

21Copyright © Prentice Hall 2000 Getting Connected User’s computer must connect to a computer called a serverUser’s computer must connect to a computer called a server Server uses Transmission Control Protocol/Internet Protocol (TCP/IP) softwareServer uses Transmission Control Protocol/Internet Protocol (TCP/IP) software YouServer

22Copyright © Prentice Hall 2000 Getting Connected Supplier of server is an ISP - Internet service providerSupplier of server is an ISP - Internet service provider YouServerISP

23Copyright © Prentice Hall 2000 Getting Around Made possible through a point-and-click browser program on the World Wide Web (WWW)Made possible through a point-and-click browser program on the World Wide Web (WWW) An Internet subset of text, images, and sounds linked togetherAn Internet subset of text, images, and sounds linked together WWW locations are web sites with main, or home pagesWWW locations are web sites with main, or home pages

24Copyright © Prentice Hall 2000 Classification of Computers SupercomputersSupercomputers MainframesMainframes Personal ComputersPersonal Computers LaptopsLaptops Personal Digital AssistantsPersonal Digital Assistants

25Copyright © Prentice Hall 2000 Supercomputers Fastest and most expensive processors on the planetFastest and most expensive processors on the planet

26Copyright © Prentice Hall 2000 Supercomputers Increasingly common in the mainstream (stock analysis, automobile design, movie effects, and sophisticated artwork)Increasingly common in the mainstream (stock analysis, automobile design, movie effects, and sophisticated artwork) Used extensively by government researchersUsed extensively by government researchers

27Copyright © Prentice Hall 2000 Mainframes Used for processing vast amounts of data quicklyUsed for processing vast amounts of data quickly Designed for multiple usersDesigned for multiple users Often known as a serverOften known as a server

28Copyright © Prentice Hall 2000 Personal Computers Low end processors and hardwareLow end processors and hardware Also known as microcomputers and home computersAlso known as microcomputers and home computers Found as workstations for engineering/financial and trade/graphic designFound as workstations for engineering/financial and trade/graphic design

29Copyright © Prentice Hall 2000 Notebook Computers Known in larger form as laptopsKnown in larger form as laptops Highly miniaturized with PC-worthy technologyHighly miniaturized with PC-worthy technology

30Copyright © Prentice Hall 2000 Smaller Still: Personal Digital Assistants Used to track appointments, other business informationUsed to track appointments, other business information Also called pen-based computers because of pen-like input stylusAlso called pen-based computers because of pen-like input stylus Include functions like wireless and fax technologyInclude functions like wireless and fax technology