Internet的發(fā)展歷史中英文

1、THEHISTORYOFTHEINTERNETTheBeginning-ARPAnetTheInternetstartedasaprojectbytheUSgovernment.Theobjectoftheprojectwastocreateameansofcommunicationsbetweenlongdistancepoints,intheeventofanationwideemergencyor,morespecifically,nuclearwar.TheprojectwascalledARPAnet,anditiswhattheInternetstartedas.Fundedspe

2、cificallyformilitarycommunication,theengineersresponsibleforARPANethadnoideaofthepossibilitiesofan"Internet."Bydefinition,an'Internet'isfourormorecomputersconnectedbyanetwork.ARPAnetachieveditsnetworkbyusingaprotocolcalledTCP/IP.Thebasicsaroundthisprotocolwasthatifinformationsentov

3、eranetworkfailedtogetthroughononeroute,itwouldfindanotherroutetoworkwith,aswellasestablishingameansforonecomputerto"talk"toanothercomputer,regardlessofwhetheritwasaPCoraMacintosh.Bythe80'sARPAnet,justyearsawayfrombecomingthemorewellknownInternet,had200computers.TheDefenseDepartment,sat

4、isfiedwithARPAnetsresults,decidedtofullyadoptitintoservice,andconnectedmanymilitarycomputersandresourcesintothenetwork.ARPAnetthenhad562computersonitsnetwork.Bytheyear1984,ithadover1000computersonitsnetwork.In1986ARPAnet(supposedly)shutdown,butonlytheorganizationshutdown,andtheexistingnetworksstille

5、xistedbetweenthemorethan1000computers.ItshutdownduetoafailiedlinkupwithNSF,whowantedtoconnectits5countywidesupercomputersintoARPAnet.WiththefundingofNSF,newhighspeedlinesweresuccessfullyinstalledatlinespeedsof56k(anormalmodemnowadays)throughtelephonelinesin1988.Bythattime,therewere28,174computersont

6、he(bythendecided)Internet.In1989therewere80,000computersonit.By1989,therewere290,000.Anothernetworkwasbuilttosupporttheincrediblenumberofpeoplejoining.Itwasconstructedin1992.Today-TheInternetToday,theInternethasbecomeoneofthemostimportanttechnologicaladvancementsinthehistoryofhumanity.Everyonewantst

7、oget'online'toexperiencethewealthofinformationoftheInternet.MillionsofpeoplenowusetheInternet,andit'spredictedthatbytheyear2003everysinglepersonontheplanetwillhaveInternetaccess.TheInternethastrulybecomeawayoflifeinourtimeandera,andisevolvingsoquicklyitshardtodeterminewhereitwillgonext,a

8、scomputerandnetworktechnologyimproveeveryday.HOWITWORKS:It'sastandardthing.PeopleusingtheInternet.Shopping,playinggames,conversinginvirtualInternetenvironments.TheInternetisnota'thing'itself.TheInternetcannotjust"crash."Itfunctionsthesamewayasthetelephonesystem,onlythereisnoInt

9、ernetcompanythatrunstheInternet.TheInternetisacollectionofmillioinsofcomputersthatareallconnectedtoeachother,orhavethemeanstoconnecttoeachother.TheInternetisjustlikeanofficenetwork,onlyithasmillionsofcomputersconnectedtoit.ThemainthingabouthowtheInternetworksiscommunication.HowdoesacomputerinHouston

10、knowhowtoaccessdataonacomputerinTokyotoviewawebpage?Internetcommunication,communicationamongcomputersconnectedtotheInternet,isbasedonalanguage.ThislanguageiscalledTCP/IP.TCP/IPestablishesalanguageforacomputertoaccessandtransmitdataovertheInternetsystem.ButTCP/IPassumesthatthereisaphysicalconnecetion

11、betweenonecomputerandanother.Thisisnotusuallythecase.TherewouldhavetobeanetworkwirethatwenttoeverycomputerconnectedtotheInternet,butthatwouldmaketheInternetimpossibletoaccess.Thephysicalconnectionthatisrequireedisestablishedbywayofmodems,phonelines,andothermodemcableconnections(likecablemodemsorDSL)

12、.Modemsoncomputersreadandtransmitdataoverestablishedlines,whichcouldbephonelinesordatalines.Theactualhardcoreconnectionsareestablishedamongcomputerscalledrouters.Arouterisacomputerthatservesasatrafficcontrollerforinformation.Toexplainthisbetter,let'slookathowastandardcomputermightviewawebpage.1.

13、 Theuser'scomputerdialsintoanInternetServiceProvider(ISP).TheISPmightinturnbeconnectedtoanotherISP,orastraightconnectionintotheInternetbackbone.2. TheuserlaunchesawebbrowserlikeNetscapeorInternetExplorerandtypesinaninternetlocationtogoto.3. Here'swherethetrickypartcomesin.First,thecomputerse

14、ndsdataaboutit'sdatarequesttoarouter.Arouterisaveryhighspeedpowerfulcomputerrunningspecialsoftware.Thecollectionofroutersintheworldmakewhatiscalleda"backbone,"onwhichallthedataontheInternetistransferred.Thebackbonepresentlyoperatesataspeedofseveralgigabytesper-second.Suchaspeedcompared

15、toanormalmodeniislikecomparingtheheatofthesuntotheheatofanice-cube.Routershandledatathatisgoingbackandforth.Arouterputssmallchunksofdataintopackagescalledpackets,whichfunctionsimilarlytoenvelopes.So,whentherequestforthewebpagegoesthrough,itusesTCP/IPprotocolstotelltherouterwhattodowiththedata,wherei

16、t'sgoing,andoverallwheretheuserwantstogo.4. Theroutersendsthesepacketstootherrouters,eventuallyleadingtothetargetcomputer.It'slikewhisperdownthelane(onlytheinformationremainsintact).5. Whentheinformationreachesthetargetwebserver,thewebserverthenbeginstosendthewebpageback.Awebserveristhecompu

17、terwherethewebpageisstoredthatisrunningaprogramthathandlesrequestsforthewebpageandsendsthewebpagetowhoeverwantstoseeit.6. Thewebpageisputinpackets,sentthroughrouters,andarriveattheuserscomputerwheretheusercanviewthewebpageonceitisassembled.Thepacketswhichcontainthedataalsocontainspecialinformationth

18、atletsroutersandothercomputersknowhowtoreassemblethedataintherightorder.Withmillionsofwebpages,andmillionsofusers,usingtheInternetisnotalwayseasyforabeginninguser,especiallyforsomeonewhoisnotentirelycomfortalewithusingcomputers.BelowyoucanfindtipstricksandhelponhowtousemainservicesoftheInternet.Befo

19、reyouaccesswebpages,youmusthaveawebbrowsertoactuallybeabletoviewthewebpages.MostInternetAccessProvidersprovideyouwithawebbrowserinthesoftwaretheyusuallygivetocustomers;you.Thefactthatyouareviewingthispagemeansthatyouhaveawebbrowser.ThetoptwousebrowsersareNetscapeCommunicatorandMicrosoftInternetExplo

20、rer.NandMSIEThefactthatyou'rereadingthisrightnowmeansthatyouhaveawebbrowser.Nextyoumustbefamiliarwithactuallyusingwebpages.Awebpageisacollectionofhyperlinks,images,text,forms,menus,andmultimedia.To"navigate"awebpage,simplyclickthelinksitprovidesorfollowit'sowninstructions(likeifith

21、asaformyouneedtouse,itwillprobablyinstructyouhowtouseit).Basically,everythingaboutawebpageismadetobeself-explanetory.Thatisthenatureofawebpage,tobeeasilynavigatable."Ohno!a404error!'Cannotfindwebpage?'"isacommonremarkmadebynewweb-users.Sometimeswebsiteshaveerrors.Butanerroronawebsi

22、teisnottheuser'sfault,ofcourse.A404errormeansthatthepageyoutriedtogotodoesnotexist.Thiscouldbebecausethesiteisstillbeingconstructedandthepagehasn'tbeencreatedyet,orbecausethesiteauthormadeatypointhepage.There'snothingmuchtodoabouta404errorexceptfore-mailingthesiteadministrator(ofthepagey

23、ouwantedtogoto)antellinghim/herabouttheerror.AJavascripterroristheresultofaprogrammingerrorintheJavascriptcodeofawebsite.NotallwebsitesutilizeJavascript,butmanydo.JavascriptisdifferentfromJava,andmostbrowsersnowsupportJavascript.Ifyouareusinganoldversionofawebbrowser(Netscape3.0forexample),youmightg

24、etJavascripterrorsbecausesitesutilizeJavascriptversionsthatyourbrowserdoesnotsupport.So,youcantrygettinganewerversionofyourwebbrowser.E-mailstandsforElectronicMail,andthat'swhatitis.E-mailenablespeopletosendletters,andevenfilesandpicturestoeachother.Tousee-mail,youmusthaveane-mailclient,whichisj

25、ustlikeapersonalpostoffice,sinceitretrievesandstorese-mail.Secondly,youmusthaveane-mailaccount.MostInternetServiceProvidersprovidefreee-mailaccount(s)forfree.Someservicesofferfreee-mail,likeHotmail,andGeocities.Afterconfiguringyoure-mailclientwithyourPOP3andSMTPserveraddress(youre-mailproviderwillgi

26、veyouthatinformation),youarereadytoreceivemail.Anattachmentisafilesentinaletter.Ifsomeonesendsyouanattachmentandyoudon'tknowwhoitis,don'trunthefile,ever.Itcouldbeavirusorsomeotherkindofnastyprograms.Youcan'tgetavirusjustbyreadinge-mail,you'llhavetophysicallyexecutesomeformofprogramfo

27、ravirustostrike.Asignatureisafeatureofmanye-mailprograms.Asignatureisaddedtotheendofeverye-mailyousendout.Youcanputatextgraphic,yourbusinessinformation,anythingyouwant.ImaginethatacomputerontheInternetisanislandinthesea.Theseaisfilledwithmillionsofislands.ThisistheInternet.Imagineanislandcommunicate

28、swithotherislandbysendingshipstootherislandsandreceivingships.Theislandhasportstoacceptandsendoutships.AcomputerontheInternethasaccessnodescalledports.Aportisjustasymbolicobjectthatallowsthecomputertooperateonanetwork(ortheInternet).Thismethodissimilartotheisland/oceansymbolismabove.Telnetreferstoac

29、cessingportsonaserverdirectlywithatextconnection.AlmosteverykindofInternetfunction,likeaccessingwebpages,"chatting,"ande-mailingisdoneoveraTelnetconnection.TelnettingrequiresaTelnetclient.AtelnetprogramcomeswiththeWindowssystem,soWindowsuserscanaccesstelnetbytypingin"telnet"(with

30、outthe"'s)intherundialog.Linuxhasitbuiltintothecommandline;telnet.ApopulartelnetprogramforMacintoshisNCSAtelnet.Anyserversoftware(webpagedaemon,chatdaemon)canbeaccessedviatelnet,althoughtheyarenotusuallymeanttobeaccessedinsuchamanner.Forinstance,itispossibletoconnectdirectlytoamailserverand

31、checkyourmailbyinterfacingwiththee-mailserversoftware,butit'seasiertouseane-mailclient(ofcourse).TherearemillionsofWebPagesthatcomefromallovertheworld,yethowwillyouknowwhattheaddressofapageyouwantis?Searchenginessavetheday.Asearchengineisaverylargewebsitethatallowsyoutosearchit'sowndatabaseo

32、fwebsites.Forinstance,ifyouwantedtofindawebsiteondogs,you'dsearchfor"dog"or"dogs"or"doginformation."Hereareafewsearch-engines.1. Altavista()-Webspider&Indexed2. Yahoo()-Webspider&IndexedCollection3. Excite()-Webspider&Indexed4. Lycos()-Webspider&Inde

33、xed5. Metasearch()-MultiplesearchAwebspiderisaprogramusedbysearchenginesthatgoesfrompagetopage,followinganylinkitcanpossiblyfind.ThismeansthatasearchenginecanliterallymapoutasmuchoftheInternetasit'sowntimeandspeedallowsfor.Anindexedcollectionuseshand-addedlinks.Forinstance,onYahoo'ssite.Youc

34、anclickonComputers&theInternet.ThenyoucanclickonHardware.ThenyoucanclickonModems,etc.,andalongthewaythroughsections,therearesitesavailablewhichrelatetowhatsectionyou'rein.Metasearchsearchesmanysearchenginesatthesametime,findingthetopchoicesfromabout10searchengines,makingsearchingalotmoreeffe

35、ctive.Onceyouareabletousesearchengines,youcaneffectivelyfindthepagesyouwant.Withthearrivalofnetworkingandmultiusersystems,securityhasalwaysbeenonthemindofsystemdevelopersandsystemoperators.SincethedawnofAT&Tanditsphonenetwork,hackershavebeenknownbymany,hackerswhofindwaysallthetimeofbreakingintos

36、ystems.Itusedtonotbethatbigofaproblem,sincenetworkingwaslimitedtobigcorporatecompaniesorgovernmentcomputerswhocouldaffordthenecessarycomputersecurity.Thebiggestproblemnow-a-daysispersonalinformation.Whyshouldyoubecarefulwhilemakingpurchasesviaawebsite?Let'slookathowtheinternetworks,quickly.Theus

37、eristransferringcreditcardinformationtoawebpage.Lookssafe,right?Notnecessarily.Astheusersubmitstheinformation,itisbeingstreamedthroughaseriesofcomputersthatmakeuptheInternetbackbone.Theinformationisinlittlechunks,inpackagescalledpackets.Here'stheproblem:Whiletheinformationisbeingtransferredthrou

38、ghthisbigbackbone,whatispreventinga"hacker"frominterceptingthisdatastreamatoneofthebackbonepoints?Big-brotherisnotwatchingyouifyouaccessawebsite,butusersshouldbeawareofpotentialthreatswhiletransmittingprivateinformation.Therearemethodsofenforcingsecurity,likepasswordprotection,anmostimport

39、antly,encryption.Encryptionmeansscramblingdataintoacodethatcanonlybeunscrambledonthe"otherend."Browser'slikeNetscapeCommunicatorandInternetExplorerfeatureencryptionsupportformakingon-linetransfers.Someencryptionsworkbetterthanothers.ThemostadvancedencryptionsystemiscalledDES(DataEncryp

40、tionStandard),anditwasadoptedbytheUSDefenseDepartmentbecauseitwasdeemedsodifficultto'crack'thattheyconsidereditasecurityriskifitwouldfallintoanothercountrieshands.ADESusesasinglekeyofinformationtounlockanentiredocument.Theproblemis,thereare75trillionpossiblekeystouse,soitisahighlydifficultsy

41、stemtobreak.Onedocumentwascrackedanddecoded,butitwasacombinedeffortof14,000computersnetworkedovertheInternetthattookawhiletodoit,somosthackersdon'thavethatmanyresourcesavailable.Internet的歷史起源ARPAnetInternet是被美國(guó)政府作為一項(xiàng)工程進(jìn)行開發(fā)的。這項(xiàng)工程的目的，是為了建立遠(yuǎn)距離之間點(diǎn)與點(diǎn)的通信，以便處理國(guó)家軍事范圍內(nèi)的緊急事件，例如核戰(zhàn)爭(zhēng)。這項(xiàng)工程被命名為ARPAnet它就是Intern

42、et的前身。建立此工程的主要應(yīng)用對(duì)象就是軍事通訊，那些負(fù)責(zé)ARPAnet的工程師們當(dāng)時(shí)也沒(méi)有想到它將成為“Internet根據(jù)定義，一個(gè)"Internet”應(yīng)該由四或者更多的計(jì)算機(jī)連接起來(lái)的網(wǎng)絡(luò)。ARPAnet是通過(guò)一種叫TCP/IP的協(xié)議實(shí)現(xiàn)連網(wǎng)工作的。此協(xié)議最基礎(chǔ)的工作原理是：如果信息在網(wǎng)絡(luò)中的一條路徑發(fā)送失敗，那么它將找到其他路徑進(jìn)行發(fā)送，就好象建立一種語(yǔ)言以便一臺(tái)計(jì)算機(jī)與其他計(jì)算機(jī)“交談”一樣，但不注意它是PG或是Macintosh。到了20世紀(jì)80年代，ARPAnet已經(jīng)開始變成目前更為有名的Internet了，它擁有200臺(tái)在線主機(jī)。國(guó)防部很滿意ARPAnets的成果，于

43、是決定全力將它培養(yǎng)為能夠聯(lián)系很多軍事主機(jī)，資源共享的服務(wù)網(wǎng)絡(luò)。到了1984年，它就已經(jīng)超過(guò)1000臺(tái)主機(jī)在線了。在1986年ARPAnet關(guān)閉了，但僅僅是建立它的機(jī)構(gòu)關(guān)閉了，而網(wǎng)絡(luò)繼續(xù)存在與超過(guò)1000臺(tái)的主機(jī)之間。由于使用NSF連接失敗，ARPAne"被關(guān)閉。NSF是將5個(gè)國(guó)家范圍內(nèi)的超級(jí)計(jì)算機(jī)連入ARPAnet隨著NSF的建立，新的高速的傳輸介質(zhì)被成功的使用，在1988年，用戶能通過(guò)56k的電話線上網(wǎng)。在那個(gè)時(shí)候有28,174臺(tái)主機(jī)連入Internet。到了1989年有80,000臺(tái)主機(jī)連入Internet。至U1989年末，就有290,000臺(tái)主機(jī)連入了。另外還有其他網(wǎng)絡(luò)被建立

44、，并支持用戶以驚人的數(shù)量接入。于1992年正式建立?，F(xiàn)狀I(lǐng)nternet如今，Internet已經(jīng)成為人類歷史上最先進(jìn)技術(shù)的一種。每個(gè)人都想“上網(wǎng)”去體驗(yàn)一下Internet中的信息財(cái)富。成千上百的人都用Internet。預(yù)計(jì)，到了2003年世界上的每個(gè)人，都將擁有Internet接入。Internet已經(jīng)真正成為我們這個(gè)年代生活的一部分。由于計(jì)算機(jī)技術(shù)和網(wǎng)絡(luò)技術(shù)每天都在改變，我們很難想象Internet下一步將發(fā)展成什么樣子。工作原理：現(xiàn)在，人們用Internet是一件很平常的事。他們通過(guò)Internet進(jìn)行購(gòu)物、玩游戲、聊天等娛樂(lè)活動(dòng)。Internet不僅僅是一件事物。Internet也會(huì)

45、崩潰。它的工作原理如同電話通信系統(tǒng)，只不過(guò)沒(méi)有專門的Internet公司來(lái)經(jīng)營(yíng)Internet。Internet是成千上萬(wàn)臺(tái)計(jì)算機(jī)互相連接的集合。Internet就像是辦公網(wǎng)絡(luò)一樣，不同的是，它有成千上萬(wàn)臺(tái)計(jì)算機(jī)相連接。其中最主要的是Internet是如何進(jìn)行通信的。位于Houston的一臺(tái)計(jì)算機(jī)是如何通過(guò)瀏覽網(wǎng)頁(yè)而能與位于Tokyo的計(jì)算機(jī)進(jìn)行數(shù)據(jù)通信的呢？Internet信息，擁有信息的計(jì)算機(jī)連接到Internet,是基于語(yǔ)言。這種語(yǔ)言叫做TCP/IP。TCP/IP建立了一種語(yǔ)言，能使計(jì)算機(jī)在Internet系統(tǒng)中傳送數(shù)據(jù)。但是TCP/IP的取得也必須具備兩臺(tái)電腦之間的物理連接。當(dāng)然也未必

46、都是這樣。但也必須存在一根網(wǎng)絡(luò)線將主機(jī)與Internet連接起來(lái)，但做到這樣，還是不可能與Internet連接的。物理連接要求通過(guò)MODEM電話線和其他類似MODEM連接（如DSL來(lái)建立。計(jì)算機(jī)上的MODEM過(guò)已建立的通信線進(jìn)行收發(fā)數(shù)據(jù)，通信線可以是電話線或是數(shù)據(jù)線。事實(shí)上計(jì)算機(jī)之間建立連接的硬核被成為路由器。路由器就是計(jì)算機(jī)中進(jìn)行信息交互的管理器。為了更好的對(duì)它說(shuō)明，讓我們來(lái)看看一臺(tái)標(biāo)準(zhǔn)的計(jì)算機(jī)是怎樣瀏覽網(wǎng)頁(yè)的？1、用戶計(jì)算機(jī)撥號(hào)進(jìn)入ISP。而此ISP可能還要連接入其他ISP,或是直接進(jìn)入Internet主干。2、用戶打開網(wǎng)頁(yè)瀏覽器如NETSCAP或是IE。3、接下來(lái)是進(jìn)入Internet的

47、棘手部分。首先，用戶計(jì)算機(jī)相路由器發(fā)出請(qǐng)求。路由器是一種高速高效的計(jì)算機(jī)運(yùn)行的專門軟件。世界上所有路由的連接便形成了Internet的主干，在這里傳送Internet上的所有數(shù)據(jù)。目前主干網(wǎng)上的處理速度為每秒幾千兆字節(jié)。這樣的速度分配到一只MODEM,就好比太陽(yáng)光的熱量分配到一塊冰上的熱量一樣。4、路由器發(fā)送或接受數(shù)據(jù)。它將一小段數(shù)據(jù)分別打包，形成數(shù)據(jù)報(bào)，就像包裹一樣。因此，當(dāng)請(qǐng)求網(wǎng)頁(yè)瀏覽是，就用TCP/IP協(xié)議告訴路由器如何處理這些數(shù)據(jù)，將這些數(shù)據(jù)發(fā)送去哪里，用戶主要想去哪里。5、路由器將這些數(shù)據(jù)報(bào)發(fā)送給其他的路由器，最終轉(zhuǎn)到目標(biāo)主機(jī)上。就像傳耳語(yǔ)的游戲一樣（當(dāng)然，只有完整的信息才能被傳送）

48、。6、當(dāng)信息到達(dá)目標(biāo)網(wǎng)頁(yè)的服務(wù)器是，服務(wù)器就開始將網(wǎng)頁(yè)信息發(fā)送回去。一臺(tái)網(wǎng)頁(yè)服務(wù)器，就是網(wǎng)頁(yè)存儲(chǔ)所在的計(jì)算機(jī)，它能對(duì)網(wǎng)頁(yè)進(jìn)行編輯，并將它發(fā)送給用戶。網(wǎng)頁(yè)被分成數(shù)據(jù)報(bào)，通過(guò)路由器，最終到達(dá)用戶計(jì)算機(jī)，這樣，用戶就能瀏覽網(wǎng)頁(yè)了。數(shù)據(jù)報(bào)中含有相關(guān)的數(shù)據(jù)以及一些必須的信息讓路由器或其他計(jì)算機(jī)知道如何將數(shù)據(jù)報(bào)按正確的順序重新組裝成原始的數(shù)據(jù)段。有了成千上萬(wàn)的網(wǎng)頁(yè)和成千上萬(wàn)的用戶，對(duì)于初學(xué)者來(lái)說(shuō)使用Internet將不再那么容易，尤其是那些不太精通電腦的人。接下來(lái)，你將能找到一些上網(wǎng)的小技巧和使用Internet主要服務(wù)的幫助。在你打開網(wǎng)頁(yè)之前,你必須有一個(gè)網(wǎng)頁(yè)瀏覽器用于瀏覽網(wǎng)頁(yè)。大部分網(wǎng)絡(luò)服務(wù)商都會(huì)給用

49、戶提供一個(gè)網(wǎng)絡(luò)瀏覽器。當(dāng)你在瀏覽網(wǎng)頁(yè)時(shí)，其實(shí)就是在使用瀏覽器。目前使用最廣泛的網(wǎng)頁(yè)瀏覽器是Netscape和MSIENetscape能自動(dòng)連接到,MSIE能自動(dòng)連接0接下來(lái)你就必須熟悉如何使用網(wǎng)頁(yè)。網(wǎng)頁(yè)是超鏈接、圖片、文本、表格、按鈕以及多媒體的集合。只需點(diǎn)擊網(wǎng)頁(yè)提供的連接或是按照網(wǎng)頁(yè)的步驟（比如，如果你需要用網(wǎng)頁(yè)中的一張表，旁邊就會(huì)有使用這張表的幫助）做，你就可以進(jìn)行網(wǎng)上沖浪了?；旧?，網(wǎng)頁(yè)中的每個(gè)元素都可以自我移植?！芭?，不！又是404出錯(cuò)！不能找到相關(guān)網(wǎng)頁(yè)”這是上網(wǎng)初學(xué)者中很普通的言論。有時(shí)網(wǎng)站也會(huì)出錯(cuò)。當(dāng)然網(wǎng)站的錯(cuò)誤跟用戶的操作沒(méi)有關(guān)系。404出錯(cuò)意思是你想找的那個(gè)網(wǎng)頁(yè)不存在。這有可能

50、是因?yàn)榫W(wǎng)站仍在建設(shè)中，頁(yè)面還沒(méi)有被創(chuàng)建，或者是因?yàn)榫W(wǎng)站的制作者正在對(duì)頁(yè)面進(jìn)行修改。當(dāng)出現(xiàn)404出錯(cuò)時(shí)，除了對(duì)網(wǎng)站管理發(fā)電子郵件，告訴他/她關(guān)于出錯(cuò)的問(wèn)題，就別無(wú)他法了。Javascript出錯(cuò)是由于網(wǎng)站中的Javascript的程序代碼出錯(cuò)造成的。并非所有的網(wǎng)頁(yè)都使用Javascript，但有很多是用Javascript的。Javascript不同于JAVA目前大部分瀏覽器都支持Javascript。如果你現(xiàn)在用的是舊版的網(wǎng)頁(yè)瀏覽器，那么就有可能出現(xiàn)Javascript出錯(cuò)，那是因?yàn)槟愕臑g覽器的版本低于站點(diǎn)使用的Javascript版本。所以，你應(yīng)該為你的瀏覽器升級(jí)到新的版本。電子郵件即電子方

51、式的郵件。電子郵件能使人們互相收發(fā)信件，甚至是文件和圖片。要使用電子郵件，那你就必須擁有一個(gè)電子郵件客戶端，它就像是郵遞員，為你收發(fā)電子郵件。其次，你必須有一個(gè)電子郵件帳戶。大部分網(wǎng)絡(luò)服務(wù)供應(yīng)商都會(huì)提供給用戶一個(gè)免費(fèi)的電子郵件帳戶。有的網(wǎng)站也提供免費(fèi)的電子郵箱，如Hotmail和Geocities配置好電子郵件客戶端，包括POP*口SMTP®務(wù)器地址（電子郵件供應(yīng)商會(huì)給你相關(guān)信息）之后，你就可以準(zhǔn)備收郵件了。附件是與信一起發(fā)過(guò)來(lái)的文件，如果有人發(fā)給你帶有附件的郵件，但你不知道他是誰(shuí)，就不要打開那個(gè)附件。它有可能是病毒或是其他惡意的程序。用戶不會(huì)通過(guò)閱讀郵件而被傳染病毒，你不得不運(yùn)行殺毒軟件來(lái)防止病毒感染。簽名是很多電子郵件程序的一個(gè)特征。簽名加在郵件的末尾。你可以將生動(dòng)的文本，你職業(yè)信息或是其他你喜歡