Indie rock is genre of alternative rock that primarily exists in the independent underground music scene. It primarily refers to rock musicians that are or were unsigned, or have signed to independent record labels, rather than major record labels. Genres or subgenres often associated with indie rock include lo-fi, post-rock, sadcore, C86, and math rock, to list but a few; other related (and sometimes overlapping) categories include shoegazing and indie pop. Indie rock artists place a premium on maintaining complete control of their music and careers, releasing albums on independent record labels (sometimes their own) and relying on touring, word-of-mouth, and airplay on independent or college radio stations for promotion. Some end up moving to major labels, often on favorable terms won by their prior independent success.

1980s

In the United Kingdom, indie music charts have been compiled since the early 1980s. Initially, the charts featured bands that emerged with a form of guitar-based alternative rock that dominated the indie charts, particularly indie pop artists such as Aztec Camera and Orange Juice, the C86 jangle-pop movement and the twee pop of Sarah Records artists. Some definitive British indie rock bands of the 1980s were The Smiths, The Stone Roses and The Jesus and Mary Chain, whose music directly influenced 1990s alternative rock movements such as shoegazing and Britpop.

In the United States, the music commonly regarded as indie rock is descended from an alternative rock scene largely influenced by the movements of the 1970s and early 1980s and their DIY ethos. In the 1980s the term "indie rock" was particularly associated with the abrasive, distortion-heavy sounds of Hüsker Dü, Dinosaur Jr, Sonic Youth, Big Black, and others that populated American indie labels, separating them from jangly college rock bands like R.E.M. and 10,000 Maniacs, who, by the end of the decade, were signed to major labels. The late eighties band Pixies is said to be the main influence in 1990s-present indie rock.Fact: date=February 2008

1990s

During the first half of the 1990s, alternative rock, led by grunge bands such as Alice in Chains, Nirvana, Soundgarden and Pearl Jam, broke into the mainstream, achieving commercial chart success and widespread exposure. Shortly thereafter the alternative genre became commercialized as mainstream success attracted major-label investment and commercially-oriented or manufactured acts with a formulaic, conservative approach. With this, the meaning of the label "alternative" changed away from its original, more counter-cultural meaning to refer to alternative music that achieved mainstream success and the term "indie rock" was used to refer to the bands and genres that remained underground. One of the defining movements of 1990s indie rock was the lo-fi movement spearheaded by Guided by Voices, Pavement, Sebadoh, The Grifters, Liz Phair, The Elephant 6 Recording Co., and others, which placed a premium on rough recording techniques, ironic detachment, and disinterest in "selling out" to the mainstream alternative rock scene.