A disc jockey, more commonly abbreviated as DJ, is a person who plays recorded music for an audience. Types of DJs include radio DJs (who host programs on music radio stations), club DJs (who work at a nightclub or music festival), mobile DJs (who are hired to work at public and private events such as weddings, parties, or festivals), and turntablists (who use record players, usually turntables, to manipulate sounds on phonograph records). Originally, the "disc" in "disc jockey" referred to shellac and later vinyl records, but nowadays DJ is used as an all-encompassing term to also describe persons who mix music from other recording media such as cassettes, CDs or digital audio files on a CDJ, controller, or even a laptop. DJs may adopt the title "DJ" in front of their real names, adopted pseudonyms, or stage names.