The hardest, loudest kind of rock music there is. Metal has been annoying your parents since the 1960s, when Black Sabbath burst out of Birmingham in a haze of occult symbolism and heady riffs while Led Zeppelin decided to take the Rolling Stones’ blues-based guitar template, but make it that little bit heavier, a lot meaner. Metal started morphing in the 1970s, with the likes of Motorhead and Judas Priest, who brought in the leather and denim and decided to speed things up, thanks to the introduction of, well, speed. Other British bands, such as Iron Maiden and Saxon, helped to make metal massive. Meanwhile, in America, Pentagram were putting their own spin on metal, slowing it down and sludging it up to create doom metal.

In the 1980s America added another new twist to metal, adding hairspray and high heels to create glam metal – think Motley Crue and even mid-period KISS. The chart friendly likes of Van Halen, Poison and Guns N’Roses swiftly followed suit, while Metallica, Slayer, Megadeth and Anthrax kept things a little more real. Later on, Pantera would slow down those groups’ thrash metal sounds and develop ‘groove metal’.

The industrial metal of groups like Ministry carried on into the 1990s with Nine Inch Nails and Marilyn Manson taking its brutalism into the mainstream, while nu-metal saw Korn, Slipknot, Linkin Park and Limp Bizkit stealing some of hip-hop’s swagger and adding it into the mix, and making teenagers worldwide get really into big baggy shorts, baseball caps and wallet chains.

Meanwhile, in Norway, black metal reigned supreme, while out in the California desert Kyuss were smoking a lot of weed and making stoner metal and in the New Orleans bayous Eyehategod were doing their own swampy thing, which was branded sludge metal.

By the 2000s, the genre had morphed again, with the development of metal-core, with bands like Converge mixing up heavy metal with hardcore punk.