In the beginning, hip-hop was club music, an offshoot of disco. After "Sucker M.C.'s," it belonged to teenagers on the street. Nothing more than brawling rhymes over a spare beat from an Oberheim DMX drum machine, the song appeared as the B side to Run-DMC's debut single, "It's Like That," and cut with sidewalk-spinning break dancers in mind. "There was never a B-boy record made until we made 'Sucker M.C.'s,'" said Run-DMC DJ Jam Master Jay. But the song's lyrics were as potent as its whiplash groove. Run charts his creation myth ("Two years ago, a friend of mine/Asked me to say some MC rhymes") before his partner introduces himself: "I'm DMC in the place to be/I go to St. John's University!" flying his alma mater like gang colors. A new school had arrived.