计算机科学导论-Chap4-OS-new.ppt

《计算机科学导论-Chap4-OS-new.ppt》由会员上传分享，免费在线阅读，更多相关内容在教育资源-天天文库。

1、1TheOperatingSystemsLayer2OutlineDefinitionCategoriesofSoftwareSystemSoftwareApplicationSoftwareOperatingsystems3ObjectivesDefinesoftware.Listthefunctionsofsystemsoftware.Listthecommonlyusedapplicationsoftware.Describeoperatingsystem.Explaintheevolutionof

2、operatingsystems.Explainhowtheoperatingsystemservesasthememorymanger,processmanager,devicemanager,andfilemanager.Recognizedifferentoperatingsystems4part1DEFINITION5Bigpicture6Whatissoftware?Acomputerhasnointelligenceofitsownandmustbesuppliedwithinstruct

3、ionsthattellitwhattodoandhowandwhentodoit.TheseinstructionsarecalledSoftware.TheU.SCopyrightActof1980definessoftwareas“asetofstatementsorinstructionstobeuseddirectlyorindirectlyinacomputerinordertobringaboutacertainresult.”7Whatissoftware?Wedefinesoftware

4、astheinstructionsandassociateddata,storedinelectronicformat,thatdirectthecomputertoaccomplishatask.“Software”isapluralnoun,sothereisnosuchthingas“softwares”or“onesoftware”.Peopleuse“softwarepackage”todescribeaparticularexampleofsoftware.8programs,dataands

5、oftwareAcomputerprogramisasetofdetailed,step-by-stepinstructionsthattellsacomputerhowtosolveaproblemorcarryoutatask.Softwareismadeupofagroupofrelatedcomputerprograms,ifthoseprogramsworktogethertocarryoutatask.Softwarealsocanincludedata,butdataaloneisnotso

6、ftware.9part2CATEGORIESOFSOFTWARE10SoftwarecategoriesComputersoftwarecanbeclassifiedinto2categories:SystemSoftwareApplicationSoftwareSystemsoftwareisthegeneralmanagerthathelpsthecomputercarryoutitsbasicoperatingtasks.Applicationsoftwareisyourservantthathe

7、lpsthehumanusercarryoutaspecifictask.11Softwarecategories12systemsoftwareSystemsoftwaredealswiththephysicalcomplexitiesofcomputerhardware.Itconsistsoffourkindsofprograms:operatingsystems,utilities,devicedrivers,andlanguagetranslators.Systemsoftwaretellsth

8、ecomputerhowtointerpretdataandinstructions;howtocommunicatewithperipheralequipmentlikeprinter,keyboardanddiskdrives;howtomanagefiles;howtousethehardwareingeneral;……13systemsoftwareOperatingsystemsareprogramsthatoper