Post on 11-Jan-2016
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An Overview of Computers
Chapter 1Chapter 1
Computer HardwareComputer Hardware
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The Big Picture
• A computer A computer system contains:system contains:
• hardware hardware (equipment)(equipment)
• software software (programs)(programs)
• people people (programmers (programmers and end-users)and end-users)
har
dw
are
software
people
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Hardware: The Basic Components of a Computer
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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
Input Processing Output
SecondaryStorage
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Input Devices
• Accept external Accept external data or data or commandscommands
Input Processing Output
SecondaryStorage
• Send data or Send data or commands to the commands to the processor processor
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Processing Unit
• Also known as Also known as the Central the Central Processing Unit Processing Unit (CPU)(CPU)
• Executes Executes computer computer instructionsinstructions
Input Processing Output
SecondaryStorage
• Manipulates input Manipulates input data into information data into information people wantpeople want
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Output Devices
• Show people the processed data in Show people the processed data in understandable terminologyunderstandable terminology
Input Processing Output
SecondaryStorage
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Storage
• Secondary storage Secondary storage devices such as devices such as disks store data disks store data and programsand programs
Input Processing Output
SecondaryStorage
• Primary storage Primary storage (or memory) (or memory) holds programs holds programs and data and data temporarilytemporarily
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Your Personal Computer Hardware
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Input: What Goes In
• Typing on a Typing on a keyboardkeyboard
• Pointing with a Pointing with a mousemouse
• Scanning with a Scanning with a wand reader or wand reader or bar-code readerbar-code reader
• May be part of a May be part of a terminalterminal
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The Processor and Memory: Data Manipulation
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The Processor
• Consists of Consists of circuits that circuits that interpret and interpret and execute program execute program instructionsinstructions
• Communicates Communicates with the input, with the input, output, and output, and storage devicesstorage devices
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Data
• The raw material The raw material to be processedto be processed
• When processed, When processed, becomes:becomes:
• Information - Information - organized, organized, meaningful, and meaningful, and useful datauseful data
101100101001010
Price: $10, Quantity: 5
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Memory
• Holds data after Holds data after input and before input and before processingprocessing
• Holds data after Holds data after processing but processing but before release to the before release to the output deviceoutput device
• Holds programs Holds programs needed by the CPUneeded by the CPU
memory chip w/package removed
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Output: What Comes Out
• Data that has Data that has been processed been processed into useful into useful informationinformation
Input Processing Output
SecondaryStorage
• Text, Text, numbers, numbers, graphics, graphics, sounds from sounds from the computer, the computer, also film, also film, voice, musicvoice, music
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Secondary Storage
• Provides Provides storage storage separate from separate from memorymemory
• Magnetic and Magnetic and optical disksoptical disks
Input Processing Output
SecondaryStorage
• Magnetic tape Magnetic tape - usually - usually cartridge cartridge format like a format like a cassettecassette
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The Complete Hardware System
• Hardware devices Hardware devices are known as are known as peripheralsperipherals– All input, output, All input, output,
and storage and storage devicesdevices
– May be as close as May be as close as the same cabinet the same cabinet or as far apart as or as far apart as separate countriesseparate countries
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Networking
• Network - a Network - a computer system computer system that uses that uses communications communications equipment to equipment to connect connect computers and computers and their resources.their resources.
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Networking
• May involve May involve phone-line phone-line connectivity connectivity through a modemthrough a modem
• Allows for Allows for services such as services such as E-mailE-mail
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The Internet
• Largest and most Largest and most far-flung network far-flung network system of them all, system of them all, connecting users connecting users worldwideworldwide
• Composed of Composed of thousands of thousands of loosely organized loosely organized component component networksnetworks
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Getting Connected
• User’s computer User’s computer must connect to a must connect to a computer called a computer called a serverserver
• Server uses Server uses Transmission Control Transmission Control Protocol/Internet Protocol/Internet Protocol (TCP/IP) Protocol (TCP/IP) softwaresoftware
You Server
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Getting Connected
• Supplier of server is an ISP - Supplier of server is an ISP - Internet service providerInternet service provider
You Server ISP
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Getting Around
• Made possible through a Made possible through a point-and-click browser point-and-click browser program on the World Wide program on the World Wide Web (WWW)Web (WWW)
• An Internet subset of text, An Internet subset of text, images, and sounds linked images, and sounds linked togethertogether
• WWW locations are web WWW locations are web sites with main, or sites with main, or home home pagespages
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Classification of Computers
• SupercomputersSupercomputers• MainframesMainframes• Personal ComputersPersonal Computers• LaptopsLaptops• Personal Digital AssistantsPersonal Digital Assistants
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Supercomputers
• Fastest and most Fastest and most expensive expensive processors on the processors on the planetplanet
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Supercomputers
• Increasingly common in the Increasingly common in the mainstream (stock mainstream (stock analysis, automobile analysis, automobile design, movie effects, and design, movie effects, and sophisticated artwork)sophisticated artwork)
• Used extensively by Used extensively by government researchersgovernment researchers
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Mainframes
• Used for Used for processing vast processing vast amounts of data amounts of data quicklyquickly
• Designed for Designed for multiple usersmultiple users
• Often known as a Often known as a serverserver
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Personal Computers
• Low end processors and Low end processors and hardwarehardware
• Also known as microcomputers Also known as microcomputers and home computersand home computers
• Found as workstations for Found as workstations for engineering/financial and engineering/financial and trade/graphic designtrade/graphic design
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Notebook Computers
• Known in larger Known in larger form as laptopsform as laptops
• Highly Highly miniaturized with miniaturized with PC-worthy PC-worthy technologytechnology
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Smaller Still: Personal Digital Assistants
• Used to track Used to track appointments, other appointments, other business informationbusiness information
• Also called Also called pen-based pen-based computerscomputers because of because of pen-like input stylus pen-like input stylus
• Include functions like Include functions like wireless e-mail and fax wireless e-mail and fax technologytechnology