Art rock is a term escribing a subgenre of rock music that tends to have "experimental or avant-garde influences" and emphasizes "novel sonic texture." Art rock is an "intrinsically album-based" form, which takes "advantage of the format's capacity for longer, more complex compositions and extended instrumental explorations. The Golden Age of Rock lectures define art rock as "a piece of music in the rock idiom that is appealing more intellectually or musically, that is, not formulated along pop lines for mass consumption." The lectures note that it is "...usually somewhat experimental", using "a long structure with several themes like classical music" or "a suite of individual songs." Art Rock "almost always features keyboards more than guitar." As well, art rock is "not so much for dancing as for listening and it often tells a story or has a philosophical theme to the lyrics."