Frankie Knuckles | Grammy-winning DJ, 59
Mr. Knuckles is considered a key figure in the evolution of the house-music genre, dating back three decades to venues in Chicago and New York.
In the late '70s, he "defined really what House music was in terms of style," said Phil White, coauthor of On the Record: The Scratch DJ Academy Guide. He would cut and tape together pieces of reel-to-reel recordings to make extended tracks.
He went on to have his own recording career, putting out albums on Virgin Records and working as a producer and remixer with many famous musicians. He had a hit with his first album's first single, "The Whistle Song," and won a Grammy in 1997 for Remixer of the Year. - AP