Screen writers in Hollywood have gone on strike after talks with studio representatives over pay collapsed.This will be the first strike by screenwriters since 1988, which lasted twenty two weeks. The Writer's Guild of America, which is 12,000 member strong, has asked all of them to stop working and set up picket lines for their protest.The dispute is over royalties as writers demanded that they are paid extra when their work is reproduced onto DVD and mobile phones. But the studios rejected their demands claiming that they were unworkable.Talk shows hosted by Jon Stewart and Jay Leno are expected to be the first to suffer, with the networks showing a string of repeats, followed by the daytime dramas which are filmed a week prior to transmission.Many movie studios have kept back a number of scripts of TV dramas in preparation for the strikes and have enough content to last until early next year.But many of America's big shows like CSI and Ugly Betty are expected to struggle and be replaced by repeats.The cost of the strike is estimated to cost $1bn.Helen Earnshaw