Rap's germination is sometimes attributed to the righteous street poetry of the Last Poets and the Watts Prophets, but it didn't begin to take full shape -- and earn its tag -- until after the Sugarhill Gang released "Rapper's Delight" in 1979. Since then, rap spread from its New York epicenter throughout the remainder of the U.S. (with each region taking on its own specific flavor) and then to countless countries. Rap's core components are beats and rhymes, but that simplicity belies the wide range of sounds that have sprung from them. Instrumentalists, a sampled breakbeat, or a drum machine can form the backbone of a track, while an arrangement can be spaciously spare or chaotically dense, and a chorus can range from atonal shouting to a sweet melody. Detractors were still calling rap a fad in 1985, when LL Cool J released his first single. They were doing the same thing when, roughly 20 years later, the same MC released his tenth album, and they'll probably continue to do so as long as the genre exists. Should rap ever die, which isn't likely, it would be far too late to prevent its effect on most other music forms, from R&B to rock to jazz.