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Indie rock is a subgenre of rock music that originated in the United Kingdom, United States and New Zealand in the early to mid-1980s. Although the term was originally used to describe rock music released through independent record labels, by the 1990s it became more widely associated with the music such bands produced.

The sound of indie rock has its origins in the New Zealand Dunedin sound of the Chills, Sneaky Feelings, Tall Dwarfs, the Clean and the Verlaines, and early 1980s college rock radio stations who would frequently play jangle pop bands like the Smiths and R.E.M.. The genre solidified itself during the mid–1980s with NME's C86 cassette in the United Kingdom and the underground success of Sonic Youth, Dinosaur Jr. and Unrest in the United States. During the decade, indie rock bands like Sonic Youth, the Pixies and Radiohead all released albums on major labels and subgenres like slowcore, Midwest emo, slacker rock and space rock began. By this time, "indie" had evolved to refer to bands whose music was released on independent record labels, in addition to the record labels themselves. As the decade progressed many individual local scenes developed their own distinct takes on the genre: baggy in Manchester; grebo in Stourbridge and Leicester; and shoegaze in London and the Thames Valley.

During the 1990s, the mainstream success of grunge and Britpop, two movements influenced by indie rock, brought increased attention to the genre and saw record labels use their independent status as a marketing tactic. This led to a split within indie rock: one side conforming to mainstream radio; the other becoming increasingly experimental. By this point, "indie rock" referred to the musical style rather than ties to the independent music scene. In the 2000s, indie rock reentered the mainstream through the garage rock and post-punk revival and the influence of the Strokes and the Libertines. This success was exacerbated in the middle of the decade by Bloc Party, the Arctic Monkeys and the Killers and indie rock proliferated into the landfill indie movement.