Origins and early development
Heavy metal developed in the late 1960s and early 1970s, largely in the United Kingdom and United States. With roots in blues rock, psychedelic rock and acid rock, heavy metal bands developed a thick, monumental sound characterized by distorted guitars, extended guitar solos, emphatic beats and loudness. In 1968 three of the genre's most famous pioneers – British bands Led Zeppelin, Black Sabbath and Deep Purple – were founded.
Evolution or diversification
Several American bands modified heavy metal into more accessible forms during the 1970s, including the raw sleazy sound and shock rock of Alice Cooper and Kiss, the blues-rooted rock of Aerosmith, and the flashy guitar leads and party rock of Van Halen. During the mid-1970s Judas Priest helped spur the genre's evolution by discarding much of its blues influence, while Motörhead introduced a punk rock sensibility and an increasing emphasis on speed. Beginning in the late 1970s bands in the new wave of British heavy metal such as Iron Maiden and Saxon followed in a similar vein, and by the end of the decade heavy metal fans became known as metalheads or headbangers. During the 1980s glam metal became popular while underground scenes produced thrash metal and other extreme subgenres such as death metal and black metal; since the mid-1990s styles have expanded to include groove metal and nu metal which often incorporates elements of grunge and hip-hop.
Cultural or musical significance
Heavy metal is traditionally characterized by loud distorted guitars, emphatic rhythms, dense bass-and-drum sound and vigorous vocals, and the typical band lineup includes a drummer, a bassist, a rhythm guitarist, a lead guitarist and a singer. The electric guitar and its amplified sonic power has historically been the key element, with heavy use of high volumes and heavy fuzz and an emphasis on guitar solos as a primary means of performer virtuosity. The lyrics of some metal genres became associated with aggression and machismo, an issue that has at times led to accusations of misogyny.
