TV-Themostimportantinventioninhumanhistory

　　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.

　　Indeed,TVhasgreatinfluenceonpeople'slife,workandstudy.