Heavy metal music
Critics disagree over who can be thought of as the first heavy metal band. Most credit either Led Zeppelin or Black Sabbath, with American commentators tending to favour Led Zeppelin and British commentators tending to favour Black Sabbath, though many give equal credit to both. A few commentators—mainly American—argue for other groups including Iron Butterfly, Steppenwolf or Blue Cheer. Deep Purple, the third band in what is sometimes considered the "unholy trinity" of heavy metal (Black Sabbath, Led Zeppelin, and Deep Purple), despite being slightly older than Black Sabbath and Led Zeppelin, fluctuated between many rock styles until late 1969 when they took a heavy metal direction.
Heavy metal music
Heavy metal's quintessential guitar style, built around distortion-heavy riffs and power chords, traces its roots to early 1950s Memphis blues guitarists such as Joe Hill Louis, Willie Johnson, and particularly Pat Hare, who captured a "grittier, nastier, more ferocious electric guitar sound" on records such as James Cotton's "" (1954); the late 1950s instrumentals of Link Wray, particularly "Rumble" (1958); the early 1960s surf rock of Dick Dale, including "Let's Go Trippin'" (1961) and "Misirlou" (1962); and The Kingsmen's version of "Louie Louie" (1963) which made it a garage rock standard.