Heavy metal is a music genre that developed out of hard rock in the '70s. It is characterized by aggressive rhythms and a powerful sound, obtained through the amplification and distortion of guitars, bass and vocals. Heavy metal was born in England. The Deep Purple are considered the pioneers of the genre, but it's only in the early 70s, with Led Zeppelin and "Paranoid" by Black Sabbath, that the genre began to detach from rock. The first experimentations happen in the suburb of Birmingham, an important industrial centre in the UK. Metal counterculture allowed many teenagers to escape from everyday life. The exasperation of the sound, style and performance responds to the need to assert one’s own identity in all its originality.
In the late '70s, with the so-called New Wave of British metal, bands like Iron Maiden, Judas Priest and Motorhead define the imaginary and the classic sound of the genre. If until then heavy metal was a typically British phenomenon, during the early 80s it spread throughout the world, laying the foundation for future subgenres. In this decade two opposing currents established themselves respectively in the charts and in the underground scene: on one side the metal pop of bands like Def Leppard, on the other one the trash metal of the American band Megadeth and Metallica with "Master of Puppets". Contaminations of punk, hardcore and metal continue throughout the decade, leading, between the 80s and 90s, to the birth of more sub-genres and the advent of Scandinavian black metal, which is still current today. The commercial success of Metal music is carried out by pop/glam metal bands such as Bon Jovi and, at the beginning of the new millennium, by the metal alternative of Marilyn Manson.
Heavy metal embodies the existential malaise of a generation that wants to vent its anger, hatred and exclusion, through a new way of understanding sound. It is based on a pessimistic vision of reality and on the concept of nihilism. The genre’s aggressiveness and antisocial tension provoked strong reactions and condemnation from society. Despite this, heavy metal is one of the most enduring and successful music genres.