计算机应用基础双语ChapterPPT课件.pptx

Chapter1 ComputerHardware 1 What sinside Inthischapter youwill GainanoverviewofcomputerequipmentandterminologyLearnhowcomputersareclassifiedLearnhowpersonalcomputersfitintothegamutofmachinesfromPDAstosupercomputersReviewbasiccomponentsofatypicalpersonalcomputersystemLookinsidethesystemunitExploreadvantagesanddisadvantagesofseveralcomputerstoragedevicesLearnsomebasicsaboutmaintainingyourcomputerandtroubleshootingproblems 2 可编辑 Whatisacomputer Adevicethat AcceptsinputProcessesdataStoresdataProducesoutput 3 可编辑 Whatisacomputer Computerinputiswhateveristyped submitted ortransmittedtoacomputersystemDatareferstosymbolsthatrepresentfacts objects andideasProcessingismanipulationofdataMosttakesplaceincentralprocessingunit CPU acomputer s brain Computerprogramsareinstructionsthattellcomputershowtoprocess 4 可编辑 Whatisacomputer AnoperatingsystemissoftwarethathelpsacomputeroperateefficientlyandkeeptrackofdataApplicationsoftwarehelpsusers apply computerstospecifictasksMemoryistemporarystorageStorageispermanentComputeroutputisresultsproducedbycomputer 5 可编辑 Whatisacomputer 6 可编辑 Howarecomputersclassified Computersaredividedintofivecategories HandheldcomputersPersonalcomputersServersMainframecomputersSupercomputers 7 可编辑 Howarecomputersclassified Handheldcomputer PDA featuresinclude Smallkeyboardortouch sensitivescreenDesignedtofitinyourpocketRunsonbatteriesUsedwhileholdingit 8 可编辑 Howarecomputersclassified ApersonalcomputerisdesignedtomeetthecomputingneedsofanindividualDesktopcomputersfitondesksandrunonpowerfromwalloutletsANotebookcomputer laptop incorporatesscreen keyboard storage andprocessing 9 可编辑 Howarecomputersclassified 10 Atabletcomputerisportable featuringatouch sensitivescreenusedforwritingordrawing Aserverisusedtoservedatatocomputersconnectedtoanetwork 可编辑 AmainframecomputeriscapableofsimultaneouslyprocessingdataforhundredsorthousandsofusersAsupercomputerisoneofthefastestcomputersintheworldandcantacklecomplextasks Howarecomputersclassified 11 可编辑 Cancomputersconnecttoeachother APDAcanconnecttodesktopwithacableorwirelesslinkPersonalcomputerscanconnecttoeachotherorlargercomputersviawiredorwirelesscomputernetworksAcomputernetworkcanbeasfewastwoorasmanyasthousandsofcomputersTheInternetistheworld slargestnetwork connectingmillionsofcomputers 12 可编辑 Cancomputersconnecttoeachother ComputerscanbeconnectedusingacentralizedmodeloradistributedmodelACentralizedcomputingsystemdependsonacentrally locatedcomputerforprocessingandstorageAdistributedcomputernetworkspreadstheprocessingandstoragetasksamongmanycomputers 13 可编辑 14 Centralizedcomputersystem Distributedcomputernetwork 可编辑 Cancomputersconnecttoeachother Cancomputersconnecttoeachother Large scalecentralizedanddistributedcomputersystemsareusedformanytasks Governmentapplicationsincludetaxrolls censusrecords andvehicleregistrationCommercialapplicationsincludeinventory payroll andpoint of saleHospitalandhealthcareorganizationsapplicationsincludepatientrecords integrateddiagnostictools patientbilling andhealthinsuranceclaimsprocessingIneducation applicationsincludecourseregistration studentrecords budgeting andpayroll 15 可编辑 Whatarethecomponentsofapersonalcomputersystem Includedinatypicalpersonalcomputersystemare SystemunitDisplaydeviceKeyboardMouse TrackpadStoragedevicesMemorycardslotsUSBportsSoundcardandspeakersWebcamNetworkcircuitryPrinter 16 可编辑 Whatarethecomponentsofapersonalcomputersystem 17 可编辑 What sinsidethesystemunit TheSystemcontainsstoragedevices apowersupply andmaincircuitboard motherboard Computerchip microchip and chip aretechnicaljargonforanintegratedcircuitAnintegratedcircuitisasuper thinsliceofsemi conductingmaterialpackedwithmicroscopiccircuitelementsAmicroprocessorisanintegratedcircuitdesignedtoprocessinstructions 18 可编辑 What sinsidethesystemunit 19 可编辑 Howdocomputercircuitsmanipulatedata Mostcomputersareelectronic digitaldevicesDigitaldevicesworkwithdiscretedata suchasdigits1and0 orlikealightswitch onoroffAnalogdevicesworkwithcontinuousdata likeadimmerswitchwithcontinuousrange 20 可编辑 Howdocomputercircuitsmanipulatedata Mostcomputersusesimplesttechnologyoftwopossiblestates likeon offswitchUsuallyweindicate on stateas1and off stateas0These1sand0sarereferredtoasbinarydigitsorshortenedtobitsComputersusesequencesofbitstodigitallyrepresentnumbers letters punctuationmarks music pictures andvideos 21 可编辑 Howdocomputercircuitsmanipulatedata Computersemployseveralcodestorepresentcharacterdata including ASCII requiresonlysevenbitsforeachcharacterExtendedASCII requireseightbitsforeachcharacterEBCDIC iseight bittechnologyusedonolder IBMmainframecomputersUnicodeusessixteenbitsandprovidescodefor65 000characters 22 可编辑 23 可编辑 Howdocomputercircuitsmanipulatedata Whatfactorsaffectcomputerspeed powerandcompatibility Computershavethreemajorcomponents ProcessorMemoryStorageWhenaprogramisstarted itismovedfromstoragetomemoryTheprocessorfetchesprograminstructionsfrommemory thenbeginstoexecute 24 可编辑 Ifinstructionsrequiredata theprocessorfetchesitfromstorage loadsitintomemory thentransfersittothemicroprocessorTheresultsaresentbacktomemoryTheresultscanbestoredorsenttooutputprinterorscreen 25 可编辑 Whatfactorsaffectcomputerspeed powerandcompatibility Speedandefficiencyofprocessingcyclecanbeaffectedbyfactorssuchas MicroprocessortypeandspeedMemorycapacityHarddiskdrivespeedandorganizationDisplaycapabilityandvideomemoryNetworkandmodemconnectionspeed 26 可编辑 Whatfactorsaffectcomputerspeed powerandcompatibility Whatfactorsaffectspeed powerandcompatibility Bitisabbreviatedaslowercase b Byteiscomposedofeightbitsandisabbreviatedbyuppercase B TheseabbreviationscombinedwithkiloproducespecificationssuchasKB kilobyte andKb kilobit 27 可编辑 Whatfactorsaffectspeed powerandcompatibility Inworldofcomputerskilomeans1024 not1000Kilobitis1024bitsandkilobyteis1024bytesKilobytesisoftenusedwhenreferringtosizeofsmallcomputerfiles 28 可编辑 Whatfactorsaffectspeed powerandcompatibility Prefix mega meansamillion orincontextofbitsandbytes 1 048 576MegabitsisusedwhenreferringtospeedofdatatransmissionMegabytesisusedwhenreferringtofilesize CDcapacity orvideocardmemorycapability 29 可编辑 Whatfactorsaffectspeed powerandcompatibility Gigareferstoabillionor1 073 741 824GigabytesareusedtodescribeRAM DVD andharddiskcapacityMainframeandsupercomputersusetera trillion peta quadrillion andexa quintillion 30 可编辑 31 可编辑 Whatfactorsaffectcomputerspeed powerandcompatibility Whatfactorsaffectspeed powerandcompatibility 32 ThethreemostpopularpersonalcomputerplatformsarePCs Macs andLinuxThePCplatformisbasedonthedesignoftheIBMPCTheMacplatformisbasedonaproprietarydesignfortheMacintoshTheLinuxplatformisastandardPCwiththeLinuxoperatingsystemCompatiblecomputersoperateinessentiallythesameway 可编辑 What simportantaboutmicroprocessors Themostimportant andusuallythemostexpensive componentofacomputerCircuitryisgroupedintoimportantfunctionalareasALU arithmeticlogicunit performsarithmeticandlogical suchascomparing operationsUsesregisterstoholddatathatisbeingprocessedControlunitdirectsmicroprocessortasks 33 可编辑 What simportantaboutmicroprocessors Microprocessorspeedismeasuredinmegahertz MHz orgigahertz GHz MHz 1millioncyclespersecondGHz 1billioncyclespersecondDuringeachcyclethemicroprocessorexecutesinstructionsThefastertheclockspeed themoreinstructionsexecutedpersecond 34 可编辑 What simportantaboutmicroprocessors MicroprocessorsarealsoratedbywordsizeManyprocessa32 bitword64 bitavailable andarefasterthen32 bitunitsMicroprocessorsmanufacturedbyseveralcompanies IntelAMDMotorolaIBM 35 可编辑 36 可编辑 What simportantaboutmicroprocessors What simportantaboutcomputermemory RAM randomaccessmemory isatemporaryholdingareafordata applicationprograminstructions andtheoperatingsystemRAMisthe waitingroom forprocessorWhenprogramisstarted itisheldinRAMuntilneededandremainsthereuntilprogramisclosed 37 可编辑 What simportantaboutcomputermemory RAMalsoholdsdataMostRAMisvolatile whichmeansitneedselectricalpowertoholddataIfpowergoesout orcomputeristurnedoff datastoredinRAMisinstantlyandpermanentlylostItisimportanttofrequentlysaveworktoapermanentstoragearea suchasharddisk asyouwork 38 可编辑 What simportantaboutcomputermemory RAMalsoholdsoperatingsysteminstructions loadedeachtimeyouturnonyourcomputerandhelduntilitisturnedoffRAMcapacityismeasuredinmegabytesorgigabytesToday scomputershavebetween512megabytesand8gigabytesofRAM 39 可编辑 40 可编辑 What simportantaboutcomputermemory What simportantaboutcomputermemory MostcomputersalsocontainROM readonlymemory atypeofmemorythatholdsthecomputer sstartuproutineWhereasRAMistemporaryandvolatile ROMispermanentandnon volatile 41 可编辑 Whydocomputersusemultiplestoragedevices Computersfeaturemultiplestoragedevices suchas Harddiskdrive themainstoragedeviceinmostcomputersProvideslotsofstoragecapacityProvidesfastaccesstofilesEconomicalCapacityismeasuredingigabytesandspeedinmilliseconds ms orrevolutionsperminute RPM 42 可编辑 43 可编辑 Whydocomputersusemultiplestoragedevices Whydocomputersusemultiplestoragedevices ACD compactdisk provides650 700MBofstorageADVD digitalvideodiskordigitalversatiledisk isavariationwithacapacityof4 7GBCanbedoubledwithduallayertechnologyBlu Rayisstoragemediumwith25GBcapacityforsinglelayerCD s DVD s andBD sare DurablestorageUnaffectedbymagneticfieldsDustanddirtcanbecleanedoffBiggestthreatarescratches 44 可编辑 Whydocomputersusemultiplestoragedevices CDsandDVDscomeinseveralvarieties Readonly ROM permanentdatastoredduringmanufacturingRecordable R Awritabledrivecanstoredatabutitcan tbechangedRewritable RW canbechangedmanytimes muchlikeaharddrivebutmuchslower 45 可编辑 AUSBflashdriveisapopularremovable portablestoragedeviceAboutthesizeofahighlighterpenVerydurableOpen edit delete andrunfilesjustasiftheywereonharddriveUsesolidstatestoragetechnologyProvidesfastaccesstodataanduseslittlepower Whydocomputersusemultiplestoragedevices 46 可编辑 Whydocomputersusemultiplestoragedevices Inadditiontostoragedevicesconnectedtocomputer datacanbestoredononlinestorage 47 可编辑 Whatkindofprotectionandmaintenancedoesacomputerrequire Largeorganizationsprotectequipmentfromtheftwithhigh techsecuritysystemsProtectpersonalcomputerbylockingtodeskorlockingroomWhentravelingbyair carryitinyourcarry onbag 48 可编辑 Whatkindofprotectionandmaintenancedoesacomputerrequire MakesurecomputerisbalancedsafelyondeskorrestingonfloorWhencarryingnotebookcomputer usepaddedcarryingcaseWhentransportingdesktop useoriginalboxorprotectitwithfoampadding 49 可编辑 Whatkindofprotectionandmaintenancedoesacomputerrequire EnvironmentalfactorscandodamageExcessheatcandamagecircuitryHighhumiditycancorrodecontactsandcablesWaterleakscanshortoutcircuitsMagneticfieldscanerasedataDust dirt andairpollutioncancauseoverheatingandclogupmechanicalparts 50 可编辑 Whatkindofprotectionandmaintenancedoesacomputerrequire RoutinecleaningofmouseandkeyboardcankeepthemworkingsmoothlyFollowmanufacturer sinstructionsforcleaningtokeepprinterfromjammingandprintheadfromsmearingKeepfloppydisksandharddisksawayfromstrongmagneticfields