Hard rock or heavy rock is a heavier subgenre of rock music typified by vocals and electric guitars that are aggressive and distorted relative to traditional rock music. Hard rock began in the mid-1960s with the garage, psychedelic and blues rock movements. Some of the earliest hard rock music was produced by the Kinks, the Who, the Yardbirds, the Rolling Stones, Cream, Vanilla Fudge, and the Jimi Hendrix Experience. In the late 1960s, bands such as Blue Cheer, the Jeff Beck Group, Iron Butterfly, Led Zeppelin, Creedence Clearwater Revival, Golden Earring, Steppenwolf, Grand Funk Railroad, Free, and Deep Purple also produced hard rock.
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