Progressive rock songs either avoid common song structures of verse, chorus, bridge, etc, or blur the formal distinctions by extending sections or inserting additional ones, for example, using musical interludes.
Progressive rock bands often use concept albums, in which a theme or storyline is explored throughout an entire album or series of albums, sometimes in a manner similar to a film or a play.
Progressive rock bands sometimes aesthetically link the music with visual art elements such as album art.
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