M.M.Palitha Mahinda MunasingheDistrict Agricultural Training Centre

Homagama -Sri Lanka

COMPUTER TECHNOLOGY

OBJECTIVES

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Identify the major types

Uses of microcomputer, midrange, and mainframe computer systems

Outline the major technologies

Uses of computer peripherals

OBJECTIVES ….

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Identify the components and functions of a computer system

Identify the computer system Peripheral

Input, Output and Storage devices

Computer Systems

End User and Enterprise Computing2008/04/06 4mmpmm

Types of Computer Systems

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All computers are systems of input, processing, output, storage, and control components

Three basic categoriesMainframeMidrange computersMicrocomputers

Types of Computer Systems …Mainframe

Enterprise systemsSuper serversTransaction processorsSupercomputers

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MidrangeNetwork serversMinicomputersWeb serversMulti-user systems

Types of Computer Systems …

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Types of Computer Systems… Microcomputers

Personal computersNetwork computersTechnical workstationsPDAsInformation appliances

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Microcomputer Systems

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The most important category of computers

• Desktop

• Laptop

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Microcomputer Systems ….

Workstation computers

Microcomputer Systems ….

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Network serversNetwork computers

Designed primarily for use with the Internet and corporate intranets

For specialized or limited computing applications

Network computers (continued)Other benefits

Ease of software distribution and licensing

Computing platform standardizationReduced end user requirementsImproved manageability

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Microcomputer Systems …

Information appliancesPDAsSet-top boxes and video-game

consolesWireless PDAsCellular and PCS phones

Microcomputer Systems…

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Microcomputer Systems …Computer terminals

Dumb terminals

Intelligent terminals

Network terminals

Transaction terminals

Midrange Computer Systems

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Multi-user systems that can manage networks of PCs and terminals

Less costly to buy, operate, and maintain than mainframes

Popular as network servers

Minicomputers

Large, fast, powerful

Handle high transaction processing volumes or complex computational problems

Super servers for large client/server networks and high-volume Internet websites

Popular for data mining and warehousing

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Mainframe Computer Systems

SupercomputersExtremely powerful systems

specifically designed for scientific, engineering, and business applications requiring extremely high speeds for massive numeric computations

Use parallel processing architectures

Process at speeds measured in gigaflops and teraflops

Mainframe Computer Systems …

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Computers are organized according to the following system functions

InputKeyboardsTouch screensPensElectronic miceOptical scannersConvert data into electronic form

The Computer System Concept

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ProcessingCentral Processing Unit (CPU)

Two sub units Arithmetic-Logic Unit (ALU) Control Unit

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The Computer System Concept …

The Computer System Concept …

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OutputVideo display unitsPrintersAudio & Video response unitsConvert electronic information

into human-intelligible form

Storage

Store data and software instructions

May also include cache memoryPrimary storage unit (hard drive)Secondary storage

Magnetic disks Optical disk drives

The Computer System Concept …

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The Computer System Concept…

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Control

The registers and other circuits of the control unit interpret software instructions and transmit directions to the other components of the computer system

The Computer System Concept…

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Computer processing speedsMilliseconds (thousandths of a second)Microseconds (millionths of a second)Nanoseconds (billionths of a second)Picoseconds (trillionths of a second)

The Computer System Concept …

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Clock speedsMegahertz (MHz)

Millions of cycles per second

Gigahertz (GHz)Billions of cycles per second

Generic name given to all input, output, and secondary storage devices

Depend on direct connections or telecommunications links to the CPU

All peripherals are online devices

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Computer Peripherals

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Computer Peripherals

Input Devices