KRS-One (born Kris Parker) was the leader of Boogie Down Productions, one of the most influential hardcore hip-hop outfits of the80s. At the height of his career — roughly 1987-1990 — KRS-One was known for his furiously political and socially conscious raps, which is the source of his nickname, "The Teacher." Around the time of 1990 s Edutainment, BDP s audience began to slip as many fans thought his raps were becoming preachy. As a reaction, KRS-One began to re-establish his street credibility with harder, sparer beats and raps. BDP s 1992 s Sex and Violence was the first sign that he was taking a harder approach, one that wasn t nearly as concerned with teaching.