Mobile phonesWhat Are Mobile Phones？A mobile phone, also known as a cellphone or cellular

A、Mobilephones
B、WhatAreMobilePhones？Amobilephone,alsoknownasacellphoneorcellularphone,isaportableelectronicdevicewhichbehavesasanormaltelephonewhilstbeingabletomoveoverawidearea(comparecordlessphonewhichactsasatelephoneonlywithinalimitedrange).Cellphonesallowconnectionstobemadetothetelephonenetwork,normallybydirectlydialingtheotherparty'snumberonaninbuiltkeypad.Mostcurrentcellphonesuseacombinationofradiowavetransmissionandconventionaltelephonecircuitswitching,thoughpacketswitchingisalreadyinuseforsomepartsofthecellphonenetwork,especiallyforservicessuchasInternetaccessandWAP.
D、Someoftheworld'slargestcellphonemanufacturersincludeAlcatel,Audiovox,Kyocera(formerlythehandsetdivisionofQualcomm),LG,Motorola,Nokia,Panasonic(MatsushitaElectric),Philips,Sagem,Samsung,Sanyo,Siemens,SKTeletech,andSonyEricsson.
E、Therearealsospecialistcommunicationsystemsrelatedto,butdistinctfromcellphones,suchassatellitephonesandProfessionalMobileRadio.
F、WorldwideDeploymentCellphoneshavealongaridvariedhistorythatstretchesbacktothe1950s,withhandhelddevicesbeingavailablesince1983.Duetotheirlowestablishmentcostsandrapiddeployment,cellphonenetworkshavesincespreadrapidlythroughouttheworld,outstrippingthegrowthoffixedtelephony.H、InmostofEurope,wealthierpartsofAsia,Australia,andtheUS,cellphonesarenowwidelyused,withthemajorityoftheadult,teenage,andevenchildpopulationowningone.ThenumberofcellphonesubscribersintheUShasreachedover190million.TheavailabilityofPrepaidorpayasyougoservices,wherethesubscriberdoesnothavetocommittoalongtermcontract,hashelpedfuelthisgrowth.I、StandardizedTechnologyJ、Thecellphonehasbecomeubiquitousbecauseoftheinteroperabilityofcellphonesacrossdifferentnetworks4ndcountries.Thisisduetotheequipmentmanufacturersallworkingtothesamestandard,particularlytheGSMstandardwhichwasdesignedforEurope-wideinteroperability.AllEuropeannationsandsomeAsiannationschoseitastheirsolestandard,whileinJapanandSouthKoreaanotherstandard,CDMA,wasselected.CellphoneCultureL、Inlessthantwentyyears,mobilephoneshavegonefrombeingrareandexpensivepiecesofequipmentusedbybusinessestoapervasivelow-costpersonalitem.Inmanycountries,cellphonesnowoutnumberlandlinetelephones,withmostadultsandmanychildrennowowningcellphones.Itisnotuncommonforyoungadultstosimplyownacellphoneinsteadofaland-linefortheirresidence.Insomedevelopingcountries,wherethereislittleexistingfixed-lineinfrastructure,themobilephonehasbecomewidespread.M、SocialLifeN、Withhighlevelsofmobiletelephonepenetration,amobileculturehasevolved,wherethephonebecomesakeysocialtool,andpeoplerelyontheircellphoneaddressbooktokeepintouchwiththeirfriends.ManypeoplekeepintouchusingSMS,andawholecultureof"texting"hasdevelopedfromthis.ThecommercialmarketinSMS'sisgrowing.ManyphonesevenofferInstantMessengerservicestoincreasethesimplicityandeaseoftextingonphones.EntertainmentP、Themobilephoneitselfhasalsobecomeatotemicandfashionobject,withusersdecorating,customizing,andaccessorizingtheircellphonestoreflecttheirpersonality.Likewise,customizedringtoneshavebeendeveloped.EtiquetteCellphoneetiquettehasbecomeanimportantissuewithmobilesringingatfunerals,weddings,moviesandplays.Usersoftenspeakatincreasedvolume,withlittleregardforothersnearbypeople.Ithasbecomecommonpracticeforplaceslikelibrariesandmovietheatrestobantheuseofcellphone
A、Y
B、N
C、NG