电视(Television)

television-----themostpervasiveandpersuasiveofmoderntechnologies,markedbyrapidchangeandgrowth-ismovingintoanewera,aneraofextraordinarysophisticationandversatility,whichpromisestoreshapeourlivesandourworld.itisanelectronicrevolutionofsorts,madepossiblebythemarriageoftelevisionandcomputertechnologies.

theword"television",derivedfromitsgreek(tele:distant)andlatin(visio:sight)roots,canliterallybeinterpretedassightfromadistance.verysimplyput,itworksinthisway:throughasophisticatedsystemofelectronics,televisionprovidesthecapabilityofconvertinganimage(focusedonaspecialphotoconductiveplatewithinacamera)intoelectronicimpulses,whichcanbesentthroughawireorcable.theseimpulses,whenfedintoareceiver(televisionset),canthenbeelectronicallyreconstitutedintothatsameimage.

televisionismorethanjustanelectronicsystem,however.itisameansofexpression,aswellasavehicleforcommunication,andassuchbecomesapowerfultoolforreachingotherhumanbeings.

thefieldoftelevisioncanbedividedintotwocategoriesdeterminedbyitsmeansoftransmission.first,thereisbroadcasttelevision,whichreachesthemassesthroughbroad-basedairwavetransmissionoftelevisionsignals.second,thereisnonbroadcasttelevision,whichprovidesfortheneedsofindividualsorspecificinterestgroupsthroughcontrolledtransmissiontechniques.

traditionally,televisionhasbeenamediumofthemasses.wearemostfamiliarwithbroadcasttelevisionbecauseithasbeenwithusforaboutthirty-sevenyearsinaformsimilartowhatexiststoday.duringthoseyears,ithasbeencontrolled,forthemostpart,bythebroadcastnetworks,abc,nbc,andcbs,whohavebeenthemajorpurveyorsofnews,information,andentertainment.thesegiantsofbroadcastinghaveactuallyshapednotonlytelevisionbutourperceptionofitaswell.wehavecometolookuponthepicturetubeasasourceofentertainment,placingourroleinthisdynamicmediumasthepassiveviewer.