Grunge (sometimes referred to as the Seattle sound) is a subgenre of alternative rock that emerged during the mid-1980s in the American state of Washington, particularly in Seattle. The early grunge movement revolved around Seattle's independent record label Sub Pop, but by the early 1990s its popularity had spread, with grunge acts in California and other parts of the U.S. building strong followings and signing major record deals.

Grunge became commercially successful in the first half of the 1990s, due mainly to the release of Nirvana's Nevermind, Pearl Jam's Ten, Soundgarden's Badmotorfinger,Alice in Chains' Dirt, and Stone Temple Pilots' Core. The success of these bands boosted the popularity of alternative rock and made grunge the most popular form ofhard rock music at the time.^[1] Although most grunge bands had disbanded or faded from view by the late 1990s, their influence continues to affect modern rock music.

Often characterized by a sludgy guitar sound that uses a high level of distortion, fuzz and feedback effects, grunge fuses elements of hardcore punk and heavy metal, although some bands performed with more emphasis on one or the other. The music shares with punk a raw sound and similar lyrical concerns.^[1] However, it also involves much slower tempos, dissonant harmonies, and more complex instrumentation—which is reminiscent of heavy metal. Lyrics are typically angst-filled, often addressing themes such as social alienation, apathy, confinement, and a desire for freedom.

Grunge bands had made inroads to the musical mainstream in the late 1980s. Soundgarden was the first grunge band to sign to a major label when they joined the roster of A&M Records in 1989. A number of factors contributed to grunge's decline in prominence. During the mid-1990s many grunge bands broke up or became less visible. Nirvana's Kurt Cobain, labeled by Time as "the John Lennon of the swinging Northwest", appeared unusually tortured by success and "struggled with an addiction to heroin before he committed suicide at the age of 27 in 1994".

Via: wikipedia