Radio drama (or audio drama, audio play, radio play,[1] radio theatre, or audio theatre) is a dramatized, purely acoustic performance. With no visual component, radio drama depends on dialogue, music and sound effects to help the listener imagine the characters and story: "It is auditory in the physical dimension but equally powerful as a visual force in the psychological dimension."[2] Radio drama includes plays specifically written for radio, docudrama, dramatized works of fiction, as well as plays originally written for the theatre, including musical theatre, and opera.