Keith Farrelle Cozart (born August 15, 1995), better known by his stage name Chief Keef, is an American rapper and record producer. Born and raised in Chicago's South Side, he began his recording career as a teenager and initially garnered regional attention and praise for his mixtapes in the early 2010s. Cozart is often credited with popularizing the hip hop subgenre drill for mainstream audiences, and is considered a progenitor of the genre.