genre of rock music often characterized by chordal guitar riffs accompanied by root notes on the bass guitar and "big" drums
Hard rock is a loosely-defined subgenre of rock music typified by a heavy use of aggressive vocals, distorted electric guitars, bass guitar, and drums, sometimes accompanied with keyboards. It began in the mid-1960s with the garage, psychedelic and blues rock movements. Hard rock developed into a major form of popular music in the 1970s, with bands such as the Who, Boston, Led Zeppelin, Deep Purple, Aerosmith, Kiss, Queen, AC/DC and Van Halen. During the 1980s, some hard-rock bands moved away from their hard-rock roots and more towards pop rock,
Established bands made a comeback in the mid-1980s and hard rock reached a commercial peak in the 1980s, with glam metal bands like Bon Jovi, and Def Leppard and the rawer sounds of Guns N' Roses, which followed up with great success in the later part of that decade.
Hard rock began losing popularity with the commercial success of R&B, hip-hop, urban pop, grunge and later Britpop in the 1990s. Despite this, many post-grunge bands adopted a hard rock sound, and the 2000s saw a renewed interest in established bands, attempts at a revival, and new hard-rock bands that emerged from the garage rock and post-punk revival scenes. Out of this movement came garage rock bands like the White Stripes, the Strokes, Interpol and, later, the Black Keys. In the 2000s only a few hard-rock bands from the 1970s and 1980s managed to sustain highly successful recording careers.
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