A rock opera is a collection of rock music songs with lyrics that relate to a common story. It is a dramatic work in which almost all of the lines are sung, and unlike traditional operas that rely on classical music, rock operas use rock music to tell their story. Rock operas are typically released as concept albums and are not scripted for acting, which distinguishes them from musicals. The themes and concepts in a rock opera are connected and often employ narrative and characters throughout. There are two main types of rock operas: the symbolic and the full. The symbolic rock opera contains no cast and exists on an audio recording only, while full rock operas contain a cast and are performed as a play. The first rock opera was a rock operetta called "A Quick One While Hes Away," a 9-minute song written by Peter Townshend for The Whos 1966 album "A Quick One". Some well-known examples of rock operas include "Tommy" by The Who, "The Rise and Fall of Ziggy Stardust and the Spiders From Mars" by David Bowie, and "Quadrophenia" by The Who.