Module5High-techLivingSection2BackgroundinformationTheHistoryoftheComputerThehistoryofcomputersstartsabout200yearsago.BlaisePascalwasfamousforbuildingthefirstdigitalcomputerin1642.LaterLeibnizinventedaspecialsteppedgearmechanism.TheprototypesmadebyPascalandLeibnizwerenotusedinmanyplaces,andconsideredstrangeuntilalittlemorethanacenturylater,whenThomasofColmarcreatedthefirstsuccessfulcalculatorthatcouldadd,subtract,multiply,anddivide.Whilehewasdevelopingthedesktopcalculator,someinterestingdevelopmentsincomputerswerestartedbyCharlesbaggageinCambridge,England.Between1850and1900greatprogressweremadeinmathematicalphysics,anditwasknownthatmostmeaningfuldynamicphenomenacouldbeidentifiedbydifferentialequationssothateasymeansfortheircalculationwouldbehelpful.Theinventionofpunchedcardswasasteptoautomatedcomputing.ThatwasusedwithcomputersbyHermanHollerithandJamesPowersin1890.Theydevelopeddevicesthatcouldreadtheinformationstoredinthecardsbythemselves.Companiessawtheseadvantagesanddevelopedbetterpunchcard,whichusedcomputersproducedbyInternationalBusinessMachines(IBM),Remington(thesamepeoplethatmakeshavers),Burroughs,andothercompanies.Thesecomputersusedelectromechanicaldevicesinwhichelectricalpowerchangedintomechanicalpower.WorldWarⅡproducedalargeneedforcomputercapacity,especiallyforthearmy.In1942,JohnP.Eckert,JohnW.Mauchly,decidedtobuildahigh-speedelectroniccomputertodothejob.ThismachinewasknownasENIAC(ElectricalNumericalIntegratorAndCalculator).Itiscommonlyconsideredthefirsthigh-speedelectronicdigitalcomputer(EDC)andwasusedfrom1946to1955.VonNeumanncontributedanewideaofhowpractical,yetfastcomputersshouldbeorganizedandbuilt.Theseideasofstored-programtechniquewereessentialandwerewidelyused.Thefirstgenerationofelectroniccomputerswiththeseadvantageswereuntilin1947.Earlyinthe50’sthediscoveriesofthemagneticcorememoryandtheTransistor-CircuitElementchangedtheimageoftheelectronic-computerfield,fromfastbutunreliablehardwaretoanimageofrelativelyhighreliabilityandevenmorecapability.1960’swasturningpoint.Inthisperiod,computerproducersbegantoprovidecomputersofdifferentpricesandcapabilities,aswellasaccessories.用心爱心专心Thetrendduringthe1970’swasmovingawayfromverypowerful,single-purposecomputersandtowardalargerrangeofapplicationsforcheapercomputersystems.Mostcontinuous-processmanufacturingnowusedcomputersofsmallercapabilityforcontrollingandregulationtheirjobs.Inthe1980’s,verylargescaleintegration(VLSI)becamepopular.Manycompanies,suchasAppleComputerandRadioShack,producedverysuccessfulpersonalcomputers(PCs)inthe1970spartlybecauseofafadincomputergames.Inthe1980sappleandIBMkeptstronginthecrowdedPCfield.Intheproductionofsemiconductorchips,theIntelandMotorolaCorporationswereverycompetitive,althoughJapanesecompaniesweremakinggreatprogress,especiallyintheareaofmemorychips.Bythelate1980s,atatime,couldprocessabout4000000instructionspersecond.Microprocessorsequippedwithread-onlymemory(ROM)nowfunctionedalotinprocess-control,testing,monitoring,anddiagnosing.CrayResearchandControlDataInc.dominatedthefieldofsupercomputers,orthemostpowerfulcomputersystems,throughthe1970sand1980s.Intheearly1980s,however,theJapanesegovernmentannouncedalargeplantodevelopanewgenerationofsupercomputers.Thisnewgeneration,theso-called“fifth”generation.Equippedwithnewtechnologiesinlargeintegration,theycanamazefeatsinthefieldofartificialintelligence,likevoicerecognition.Progressinsoftwarehasnotmatchedthegreatadvancesinhardware.Softwareisthemaincostofmanysystemsbecauseprogrammingproductivityhasnotincreasedquickly.Newprogrammingtechniques.Suchasobject-orientedprogramming,havebeendevelopedtosolvethisproblem.Despitedifficultieswithsoftware,however,thecostpercalculationofcomputersisrapidlydecreasing,whiletheirabilitieswillincreaseintheearlyfuture.Thecomputerfieldcontinuestoexperiencehugegrowth.Computernetworking,computermail,andelectronicpublishingarejustafewoftheapplicationsinrecentyears.Progressintechnologiescontinuestoproducecheaperandmorepowerfulcomputers.Itshowsthatinthenearfuture,computersorterminalswillenterintomost,ifnotallhomes,offices,andschools.用心爱心专心
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