Thrash metal is an extreme subgenre of heavy metal music characterized by its fast tempo and overall aggression. The songs usually use fast percussive beats and low-register guitar riffs, overlaid with shredding-style lead work. The lyrics often deal with social issues and reproach for The Establishment, using direct and denunciatory language, an approach which partially overlaps with the hardcore genre.
The genre evolved in the early 1980s from combining the drum beats of hardcore punk with the guitar style of the New Wave of British Heavy Metal. It emerged partially as a reaction to the more conventional and widely acceptable glam metal, a less aggressive, pop music-infused heavy metal subgenre which appeared simultaneously. Thrash metal was an inspiration for subsequent extreme genres such as death metal and black metal.
Four American bands, Anthrax, Megadeth, Metallica, and Slayer, are credited with pioneering and popularizing the genre. The Clash of the Titans tour (1990–1991), which featured Megadeth, Slayer, and Anthrax, is considered the genre’s pinnacle, after which thrash metal saw a decline in popularity throughout the decade. Thrash metal has seen a resurgence in recent times, with many of the older bands returning to their roots with their new releases. A new generation of thrash metal bands emerged in the early 2000s, drawing lyrical and visual inspiration from the older groups.