▁contemporary ▁popular ▁cultural ▁sens ations . ▁Many ▁Americans ▁learn ▁the ▁significance ▁of ▁historical ▁events ▁and ▁political ▁issues ▁through ▁news ▁media , ▁as ▁they ▁are ▁presented ▁on ▁popular ▁news ▁stations . ▁However , ▁journal istic ▁influence ▁is ▁growing ▁less ▁important , ▁whereas ▁social ▁networking ▁sites ▁such ▁as ▁Facebook , ▁YouTube ▁and ▁Twitter , ▁provide ▁a ▁constant ▁supply ▁of ▁alternative ▁news ▁sources ▁for ▁users . ▁ ▁As ▁social ▁networking ▁becomes ▁more ▁popular ▁among ▁older ▁and ▁younger ▁gener ations , ▁sites ▁such ▁as ▁Facebook ▁and ▁YouTube , ▁gradually ▁und erm ine ▁the ▁tradition ally ▁author itative ▁voices ▁of ▁news ▁media . ▁For ▁example , ▁American ▁citizens ▁contest ▁media ▁coverage ▁of ▁various ▁social ▁and ▁political ▁events ▁as ▁they ▁see ▁fit , ▁inserting ▁their ▁voices ▁into ▁the ▁narr atives ▁about ▁America ' s ▁past ▁and ▁present ▁and ▁sh aping ▁their ▁own ▁collect ive ▁mem ories . ▁An ▁example ▁of ▁this ▁is ▁the ▁public ▁explos ion ▁of ▁the ▁T ray von ▁Martin ▁shooting ▁in ▁San ford , ▁Florida . ▁News ▁media ▁coverage ▁of ▁the ▁incident ▁was ▁minimal ▁until ▁social ▁media ▁users ▁made ▁the ▁story ▁recogn izable ▁through ▁their ▁constant ▁discussion ▁of ▁the ▁case . ▁Appro xim ately ▁one ▁month ▁after ▁the ▁fatal ▁shooting ▁of ▁T ray von ▁Martin , ▁its ▁online ▁coverage ▁by ▁every day ▁Americans ▁gar ner ed ▁national ▁attention ▁from ▁main stream ▁media ▁journal ists , ▁in ▁turn ▁exempl ifying ▁media ▁activ ism . ▁In ▁some ▁ways , ▁the ▁spread ▁of ▁this ▁trag ic ▁event ▁through ▁alternative ▁news ▁sources ▁par alle ls ▁that ▁of ▁Em mitt ▁Till