Hard rock or heavy rock is a heavier subgenre of rock music typified by aggressive vocals and distorted electric guitars. 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 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, Golden Earring, Steppenwolf, and Deep Purple also produced hard rock.

Vanilla Fudge is an American rock band known predominantly for their slow extended heavy rock arrangements of contemporary hit songs, such as their hit cover of the Supremes' "You Keep Me Hangin' On".