John R. Austin II, better known by his stage name Ras Kass, is an American rapper. He is a member of the hip hop supergroup The HRSMN, along with Canibus, Killah Priest, and Kurupt in 2014. He is also a member of the group Golden State Warriors with Xzibit and Saafir. About.com ranked him No. 30 on their list of the Top 50 MCs of Our Time (1987–2007), while Pitchfork Media called him "one of the best rappers of all time."

Rapping is an artistic form of vocal delivery and emotive expression that incorporates "rhyme, rhythmic speech, and [commonly] street vernacular". It is usually performed over a backing beat or musical accompaniment. The components of rap include "content", "flow", and "delivery". Rap differs from spoken-word poetry in that it is usually performed off-time to musical accompaniment. It also differs from singing, which varies in pitch and does not always include words. Because they do not rely on pitch inflection, some rap artists may play with timbre or other vocal qualities. Rap is a primary ingredient of hip hop music, and so commonly associated with that genre that it is sometimes called "rap music".