computer basics1

8/8/2019 Computer Basics1

1/43

COMPUTERBASICS


2/43

WhatisaComputer?

Anelectronicdevice that stores, retrieves,and processes data, and can beprogrammed with instructions. Acomputer is co

mposed of hard

ware and

software, and canexist in a variety ofsizesandconfigurations.


3/43

Hardware&SoftwareThe term hardware refers to the physical

components of your computer such as thesystemunit,mouse,keyboard,monitoretc.

The software is the instructions thatmakesthe computer work. Software is held eitheron your computers hard disk, CD-ROM,DVD or on a disket te (floppy disk) and is

loaded (i.e. copied) from the disk into thecomputers RAM (Random Ac ces s Memory),asandwhenrequired.


4/43

TypesofComputersMiniandMainframeComputers

Very powerful, used by large

organisations such an banksto control

the entire business operation. Veryexpensive!

PersonalComputersCheap and easy to use. Often used asstand-alonecomputersor inanetwork.May be connected to large mainframecomputerswithinbigcompanies.


5/43

HardwareComponentsInputDevices--"Howtotellitwhattodo

-Akeyboardandmousearethestandardwaytointeract with the computer. Other devices include

joysticksandgamepadsusedprimari lyforgames.OutputDevices--"Howitshowsyouwhatitisdoing"

- The monitor (the screen) is how the computer

sends information back to you. A printer is also an

outputdevice.


6/43

HardwareComponentsINPUTDEVICES TheMouse

UsedtodriveMicrosoftWindows TheKeyboard

Thekeyboardissti l lthecommonestwayofenteringinformationintoacomputer

TrackerBal ls analternativetothetraditionalmouseandoftenusedbygraphicdesigners


7/43

HardwareComponentsINPUTDEVICES Scanners

A scanner al lows you to scan printed material

and convert it into a fi le format that may beusedwithinthePC

TouchPads A device that lays on the desktop and

respondstopressure LightPens

Used to al low users to point to areas on a

screen

Joysticks

Many games require a joystick for the proper

playingofthegame


8/43

HardwareComponentsOUTPUTDEVICES VDU

Thecomputerscreen isusedforoutputtinginformationinanunderstandableformat

Printers

Therearemanydifferent typesofprinters. In large organizations laser printers aremost commonly used due to the fact thatthey can print very fast and give a veryhighqualityoutput.


9/43

HardwareComponentsOUTPUTDEVICES Plot ters

Aplotter isanoutputdevicesimi lartoaprinter,butnormal lyal lowsyou toprintlargerimages.

Speakers

Enhancesthevalueofeducationalandpresentationproducts.

Speechsynthesisers Givesyou theabil itytonotonly todisplay

textonamonitorbutalsotoreadthetexttoyou


10/43

HardwareComponentsStorageDevices--"Howitsavesdataandprograms

-Harddiskdrivesareaninternal,highercapacitydrivewhichalsostorestheoperatingsystemwhichrunswhenyoupoweronthecomputer.

-"Floppy"diskdrivesal lowyoutosaveworkonsmal ldisksandtakethedatawithyou.


11/43

HardwareComponentsHardDisks Speed:

Veryfast ! Thespeedofaharddiskisoftenquotedas"average

ac cesstime"speed,measuredinmi lliseconds. Thesmal lerthisnumberthefasterthedisk.

Capacity:

Enormous! Often40/80Gigabytes. AGigabyteisequ

iva

len

tto

1024

Megaby

tes.

Cost:

Harddiskscostsarefal l ingrapidlyandnormal lyrepresentthecheapestwayofstoringdata.


12/43

HardwareComponentsDisket tes(FloppyDisks) Speed:

Veryslow! Capacity:

Normal ly1.44Mbytes. Cost:

Verycheap.


13/43

HardwareComponentsCD-ROM Disks Speed:

Muchslower

than

hard

d

isks. The

or

ig

ina

l

CD-ROMspeciationisgivenavalueof1xspeed,andlater,fasterCD-ROMsarequotedasamultipleofthisvalue.

Capacity:

Around650Mbytesandmore


14/43

HardwareComponentsDVDDrives Speed:

Much

fas

ter

than

CD-R

OMdr

ives

bu

t

notasfastasharddisks. Capacity:

Upto17Gbytes. Cost:

Sl ightlyhigherthanCD-ROMdrives.


15/43

MainPartsofComputerMemory--"Howtheproces sorstoresandusesimm ediatedata RAM-RandomAccessMemory

Thema

in

'work

ing

'memory

used

by

the

computer.

Whentheoperatingsystemloadsfromdiskwhenyoufirstswitchonthecomputer,itiscopiedintoRAM.

Asa

rough

ru

le,

a

Microso

ftWindo

wsbased

compu

ter

wil loperatefasterifyouinstallmoreRAM.DataandprogramsstoredinRAMarevolati le(i.e.theinformationislostwhenyouswitchoffthecomputer).


16/43

HardwareComponentsMemory

ROMReadOnlyMemory ReadOnlyMemory(ROM)asthenamesuggestsisaspecial

typeofmemorychipthatholdssoftwarethatcanbereadbutnotwrit tento.

AgoodexampleistheROM-BIOSchip,whichcontainsread-onlysoftware.

OftennetworkcardsandvideocardsalsocontainROMchips.


17/43

HardwareComponentsHowComputerMemoryIsMeasured Bit

Allcomputersworkonabinarynumberingsystem,i.e.theyprocessdatainone'sorzero's. This1or0levelofstorageiscal ledabit.

Byte

Abyteconsistsofeightbits. Ki lobyte

Aki lobyte(KB)consistsof1024bytes. Megabyte

Amegabyte(MB)consistsof1024ki lobytes. Gigabyte

Agigabyte(GB)consistsof1024megabytes.


18/43

HardwareComponentsMicroprocessors--"Thebrainofthecomputer-PCsprimari lyusemicroproces sors(sometimescal ledthechip).TheolderIntelversionsincludethe386,486andnowthePentiuml ine.

The CPU (Central Processing Unit) is normal lyan Intel

Pentium (or equivalent) and it is one of the most important

componentswithinyourcomputer. It determines how fast your computer wil l run and is

measuredbyitsMHzspeed. Thus a 600 MHz Pentium is much faster than say a 400

MHzPentiumCPU. It is the CPU that performs all the calculations within

thecomputer.


19/43

HardwareComponentsSomeoftheFactors

ThatImpactonaComputer'sPerformance CPUspeed RAMsize Harddiskspeedandcapacity


20/43

SoftwareComponentOperatingsystemssoftware

The operating system is a special type of program that loads

automatical lywhenyoustartyourcomputer.Theoperatingsystemal lowsyoutousetheadvancedfeaturesofamoderncomputerwithouthaving to learnall thedetai lsofhowthehardwareworks

Thel inkbetweenthehardwareandyou,theuserMakesthecomputereasytousewithouthavingtounderstandbitsandbytes!


21/43

SoftwareComponent

Appl icationssoftwareAn application program is the type of program that

youuseoncetheoperatingsystemhasbeenloaded.Examples include word-proces sing programs,

spreadsheetsanddatabases


22/43

SoftwareComponentAppl icationSoftware Wordprocessingappl ications

Microsoft Word

Lotus

Word

Pro

WordPerfect

Spreadsheets

MicrosoftExcel

Lotus

123

Database

MicrosoftAcces s LotusApproach


23/43

SoftwareComponentAppl icationSoftware Payrol l

Sagesoftware

Presentationtools

MicrosoftPowerPoint LotusFreelance

Desktoppubl ishing A

bodePho

toshop

Multimediaappl ications Microsoft'sEncartaCD-ROMbasedencyclopaedias


24/43

InformationNetwork LAN

ALAN(LocalAreaNetwork) isasystemwherebyindividualPCsareconnectedtogetherwithinacompany

or

organ

iza

tion

WAN

AWAN(WideAreaNetwork)asthename impl iesal lowsyou toconnect toothercomputersoverawiderarea(i.e.thewholeworld).


25/43

InformationNetworkUsesofNetwork

Iftenpeopleareworkingtogetherwithinanofficeitmakes

sense

for

them

al lto

be

connec

ted.

In this way the office can have a single printer

andalltenpeoplecanprinttoit. Inasimi larwayotherdevicessuchasmodemsor

scannerscanbeshared. Even more useful is the abi lity to share

informationwhenconnectedtoanetwork.


26/43

ComputerAccessories Modem

Short for MODulate/DEModulate. The modem

sends information from your computer across thetelephonesystem.

The modem at the other end of the phone l ine,

converts thesignalback intoa format thatcanbeused

by

the

re

ce

iv

ing

com

puter.


27/43

UsesofComputerPCatHomeCommonusesforthecomputerwithinthehome

Computergames WorkingfromHome BankingfromHome ConnectingtotheWeb


28/43

UsesofComputerComputersinEducation CBT(ComputerBasedTraining)

ComputerBasedTraining(CBT)offersalowcostsolutiontotrainingneedswhereyouneedtotrainalargeamountofpeopleonasinglesubject.

Theseprogramsarenormal lysuppl iedonCD-ROMandcombinetext,graphicsandsound.

Packagesrangefromgeneralencyclopaediasrightthroughtolearningaforeignlanguage.


29/43

UsesofComputerOfficeAppl ications AutomatedProductionSystems

Manycarfactoriesarealmostcompletelyautomatedandthecarsareas sembledbycomputer-control ledrobots.

This automation is becoming increasingly common

throughoutindustry. DesignSystems

Many products are designed using CAD (Computer AidedDesign) programs to produce exact specificationsanddetai leddrawingson thecomputerbeforeproducingmodelsofnewproducts.


30/43

UsesofComputerOfficeAppl ications StockControl

Stockcontrol is idealforautomationand inmanycompaniesit

is

now

completely

computerized.

Thestockcontrolsystemkeepstrackofthenumberof itemsin stock and can automatical ly order replacement items

whenrequired. Ac counts/Payroll

Inmost large organizations the ac counts aremaintainedbyacomputerizedsystem.

Due to the repetitivenatureofac countsacomputersystemisideal lysuitedtothistaskandac curacyisguaranteed.


31/43

UsesofComputerComputersinDai lyLife Ac counts

Games

Educational

On-linebanking Smart ID cards Supermarkets

Workingfromhome(Tele-working) Internet


32/43

CreateaGoodWorkingEnvironment Frequentbreaksawayfromthecomputer Appropriatepositioningofscreens,chairsandkeyboa

rds

Provisionofadequatel ightingandventi lation.


33/43

Health&SafetyPrecautions Makesurethatcablesaresafelysecured Makesurethatpowerpointsarenotoverloaded Alsobeawareof:

RepetitiveStrainInjury(RSI) Glarefromscreens B

adpos

ture


34/43

ValueofBackup The most important thing that you store

onyourcomputerisinformation. Often the contents of a hard disk can

representyearsofwork. Iftheharddiskstopsworkingonedayyou

couldloseallthoseyearsofwork. For this reason it is VITAL that you take

regular backups of the information that isstoredonthecomputer.


35/43

ValueofBackup Organizeyourcomputerformoreef ficientbackups

Completevs.incrementalbackups Use'of f-site'storage


36/43

ValueofBackup Usepasswords UnderstandtheImportanceofshuttingdownyourcomputerproperly

UseaUPS(Un-inter ruptiblePowerSupply)


37/43

Likes&DislikesofComputer Thingscomputerlike:

Goodventilation Cleanenvironment Stable,vibrationfreesurface

Thingscomputerdontl ike: Dust

Drinkingandeatingoverthekeyboard Heat,ColdorMoisture Dontplaceobjectsontopofmonitors. Dontplacefloppydisksnearmonitors.


38/43

ComputerVirus What are computer viruses?

Viruses are smal l programsthat hide themselves on your

disks (both disket tes andyourharddisk). Unless you use virus

detection software thefirsttime that youknow that you

have a virus is when itactivates.

Different viruses are

activatedindif ferentways.


39/43

ComputerVirus HowdovirusesinfectPCs?

Viruses hide on a disk and whenyouac cess the disk (either a

disket te or another hard diskoveranetwork) thevirus program

wi ll start and infect yourcomputer.

The worst thing about a computervirus is that theycanspread fromonecomputer toanother,eitherviauseofinfected floppy disk, or over a

computer network, including the

Internet.


40/43

ComputerVirus Howtopreventvirusdamage

There are a number of third party anti-

virusproductsavai lable. Most of these are bet ter than theratherrudimentary products

avai lable withinDOS andWindows, but of course you dohave topayforthem!

Themain thing about your viruscheckeristhatitshouldbekeptuptodate.

Many companies supplyupdateddisksona regular basis or al low you to receive

updates through an electronic, on-l inebu

l letin

board.


41/43

SoftwareCopyright

Beawareonsoftwarecopyrightis sues Freeware

Shareware

WhataboutsoftwarethatyoufindontheInternet?

Softwaresitel icenses


42/43

SoftwareCopyright

If your computer system holds

informationabout individuals thenyouhave a moral and legal duty to treat

thatinformationwithrespect. In a free society you have a right to

ensure that information held about

youisnotabused. In many countries this right is

enshrinedunderdataprotectionlaws


43/43

NowLetusstartourComputers

andgetgoing

computer basics1

Documents