"P.S.K. What Does It Mean?" (also written as "P.S.K. (What Does It Mean?)") is a song released in 1985 by Philadelphia rapper Schoolly D on his independent label Schoolly D Records. P.S.K. are the initials for Park Side Killas, a street gang with which Schoolly D was affiliated. The highly influential song is considered the first hardcore rap song and features incidents of graphic sex, gunplay, drug references and one of the first uses of the word "nigga" in a rap song (earlier uses include Scoopy Rap and Family Rap in 1979, and New York New York in 1983).
It would be critical to the rise of West Coast gangsta rap when the street hustler, gang member and upcoming rapper by the name of Ice-T released his hardcore anthem "6 in the Mornin'" that he has admitted in interviews was written after he heard Schoolly D's "P.S.K." Eazy-E's first song "Boyz-N-The-Hood is also heavily influenced by "P.S.K." Another fan of the song is musician Moby and Danny Diablo, who covered it with the Lordz of Brooklyn.