The most striking tendency and identifying feature of any given piece of progressive rock is that it feels carefully composed, yet spontaneous and improvised at the same time. Progressive rock lends itself as much to intellectual analysis as it does to emotional enjoyment.
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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