A disc jockey, more commonly abbreviated as DJ, is a person who plays recorded music for an audience. Most common types of DJs include radio DJs, club DJs, mobile DJs, and turntablists. 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.