DictionaryAdictionaryisacollectionofwordsinoneormorespecificlanguages,oftenlistedalphabetically,withusageofinformation,definitions,etymologies,phonetics,pronunciations,translation,andotherinformation;orabookofwordsinonelanguagewiththeirequivalentsinanother,alsoknownasalexicon.Itisalexicographicalproductdesignedforutilityandfunction,curatedwithselecteddata,presentedinawaythatshowsinter-relationshipsamongthedata.ThebeginningofEnglishdictionariesdatefrom1604whenthefirst“hard-workdictionary”,whichcontainedfewerthan3000difficultwords,waspublished.Butanimportantprinciplewasintroducedthatoflistingwordsinalphabeticalorder.TheUniversalEtymologicalEnglishDictionary,thefirstmajordictionarythatcontainedabout40,000words,publishedin1721.In1755,oneofthegreatlandmarksinthehistoryofdictionarieswasthepublicationofADictionaryoftheEnglishLanguagebySamuelJohnson.InAmerica,in1828,AnAmericanDictionaryoftheEnglishLanguage,whichincludedAmericanpronunciationandspelling,waspublished.Probably,themostimportantdevelopmentinthehistoryofdictionarieswastheproductionofTheOxfordEnglishDictionarywhichwaseditedbyDr.JamesMurrayin1879andfinishedin1928with500,000words.Inageneraldictionary,eachwordmayhavemultiplemeanings.Somedictionariesincludeeachseparatemeaningintheorderofmostcommonusagewhileotherslistdefinitionsinhistoricalorder,withtheoldestusagefirst.Inmanylanguages,wordscanappearinmanydifferentforms,butonlytheundeclinedorunconjugatedformappearsastheheadwordinmostdictionaries.Dictionariesaremostcommonlyfoundintheformofabook,butsomenewerdictionaries,likeStarDictandtheNewOxfordAmericanDictionaryaredictionarysoftwarerunningonPDAsorcomputers.TherearealsomanyonlinedictionariesaccessibleviatheInternet.Incontrasttotraditionaldictionaries,whicharedesignedtobeusedbyhumanbeings,dictionariesfornaturallanguageprocessingarebuilttobeusedbycomputerprograms.Thefinaluserisahumanbeingbutthedirectuserisaprogram.Suchadictionarydoesnotneedtobeabletobeprintedonpaper.Thestructureofthecontentisnotlinear,orderedentrybyentrybuthastheformofacomplexnetwork.Becausemostofthesedictionariesareusedtocontrolmachinetranslationsorcross-lingualinformationretrievalthecontentisusuallymultilingualandusuallyofhugesize.Inordertoallowformalizedexchangeandmergingofdictionaries,anISOstandardcalledLexicalMarkupFrameworkhasbeendefinedandusedamongtheindustrialandacademiccommunity.Inmyopinion,thehistoryofdictionariesisalsothedevelopmentoftheEnglish.AsweallknowthatakindofEnglishchangesconstantly,sowehavetoupdatethemcontinuouslysothatwecanfindthenewestdefinitionofawordinthedictionaryandletithelpusknowtheaccuratemeaningofaword.AsaEnglishmajor,IthinkweshoulduseEnglishdictionaryinaproperwaysothatwecanimproveourquantityofEnglishvocabulary.Allinall,Ithinkdictionaryisagoodassistanttous,soweshouldmakefulluseofthem..