Yasiin Bey, better known by his stage name Mos Def (/ˌmoʊs ˈdɛf/), is an American rapper, singer, songwriter, and actor. Best known for his music, Bey began his hip hop career in 1994, alongside his siblings in the short-lived rap group Urban Thermo Dynamics (UTD), after which he appeared on albums by Da Bush Babees and De La Soul.
