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Because there are so many varieties, "rock" is often accompanied by a descriptor, as in indie rock or folk rock. Descended from the early rock and roll of the '50s, rock branched out into a variety of forms but still usually centers on electric guitars, bass guitar, and drums. Rock is frequently in a 4/4 time signature and uses a verse-chorus format.
Listen to all sounds and mixes. You have the choice: Classic Rock, Hard Rock, Alternative Rock, Guitar, Indie, Rock, Guitar Rock, Pop, Folk Rock, Soundtrack, Singer Songwriter, Dance, Film Music, Folk, Acoustic, Gospel, Pop Rock, TV Music, Guitar Music, Progressive Rock are the most common styles where artists uploaded their music and sounds.