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.
Music of the United States
Heavy metal is characterized by aggressive, driving rhythms, amplified and distorted guitars, grandiose lyrics, and virtuosic instrumentation. Heavy metal's origins lie in the hard rock bands who took blues and rock and created a heavy sound built on guitar and drums. Most of the pioneers in the field were British; the first major American bands came in the early 1970s, like Blue Öyster Cult, KISS, and Aerosmith. Heavy metal remained, however, a largely underground phenomenon. During the 1980s the first major pop-metal style arose and dominated the charts for several years kicked off by metal act Quiet Riot and dominated by bands such as Mötley Crüe and Ratt; this was glam metal, a hard rock and pop fusion with a raucous spirit and a glam-influenced visual aesthetic. Some of these bands, like Bon Jovi, became international stars. The band Guns N' Roses rose to fame near the end of the decade with an image that was a reaction against the glam metal aesthetic.