Heavy metal (often referred to simply as metal) is a subgenre of rock music that developed in the late 1960s and early 1970s. With roots in blues-rock and psychedelic rock, the bands that created heavy metal developed a thick, massive sound characterized by highly amplified distortion and extended guitar solos. Allmusic states that, “of all rock & roll’s myriad forms, heavy metal is the most extreme in terms of volume, machismo and theatricality.”
Heavy metal has long had a worldwide following of fans known as metalheads or headbangers. Although early heavy metal bands such as Black Sabbath, Led Zeppelin and Deep Purple attracted large audiences, they were often critically reviled at the time. A status common throughout the history of the genre. In the mid-1970s, Judas Priest helped spur the genre’s evolution by discarding much of its blues influence. Bands in the New Wave of British Heavy Metal such as Iron Maiden and Motörhead followed in a similar vein, introducing a punk rock sensibility and an increasing emphasis on speed.
In the mid-1980s, pop-infused glam metal became a major commercial force with groups like Mötley Crüe. Underground scenes produced an array of more extreme, aggressive styles: thrash metal broke into the mainstream with bands such as Metallica, also leading the development of more extreme styles, such as death metal and black metal, which remain subcultural phenomena. Alternative Metal later followed these, as a reaction to both: being more accessible than the extreme styles typified by death metal (while not as overtly commercial as hair metal) while also being musically varied and sonically adventurous. Since the mid-1990s, popular styles such as nu metal, which often incorporates elements of funk and hip hop; and metalcore, which blends extreme metal with hardcore punk, have further expanded the definition of the genre.
Other subgenres of metal include power metal, speed metal, melodic death metal (also known as Gothenburg metal), Industrial metal, nu-metal, thrash metal, black metal, doom metal, death metal, progressive metal and folk metal. .