From 1954 to 1984, the media made rock n' roll an international language. In this era of rapidly changing technology, styles and culture changed dramatically, too. In the 1950s, wild-eyed Southern boys burst into national consciousness on 45 rpm records, and then 1960s British rockers made the transition from 45s to LPs. By the 1970s, rockers were competing with television, and soon MTV made obsolete the music-only formats that had first popularized...