Jason William Mizell (January 21, 1965 – October 30, 2002), better known by his stage name Jam Master Jay, was an American musician and rapper. He was the DJ of the influential hip hop group Run-D.M.C. and helped define the sound of the band, the style of the black hats and Adidas shoes that came to be the band’s trademark. During the 1980s, Run-D.M.C. became the biggest hip-hop group and are credited with breaking hip-hop into mainstream music.