Dante Terrell Smith (born December 11, 1973) is an American actor and emcee known by the stage names Mos Def and Yasiin Bey. He started his hip hop career in a group called Urban Thermo Dynamics, after which he appeared on albums by Da Bush Babees and De La Soul. With Talib Kweli, he formed the duo Black Star, which released the album Black Star in 1998. He was a major force in late 1990s underground hip hop while with Rawkus Records. As a solo artist he has released the albums Black on Both Sides in 1999, The New Danger in 2004, True Magic in 2006, and The Ecstatic in 2009. Although he was initially recognized for his musical output, since the early 2000s, Mos Def's screen work has established him as one of only a handful of rappers who have garnered critical approval for their acting work. Mos Def has also been active in several social and political causes.