Sometimes referred to as the Seattle Sound, is a genre of alternative rock inspired by hardcore punk, heavy metal and indie rock.

Grunge was created in the mid-1980s by bands from the Seattle area. Grunge became commercially successful in the first half of the 1990s, due mainly to the release of Nirvana's Nevermind and Pearl Jam's Ten. The genre is closely associated with Generation X in the US, since the popularity of the genre and usage of the generational term rose simultaneously. Grunge was an early defining musical phenomenon of the 1990s, which distinguished 1990s rock music from that of the 1980s.

Grunge music is generally characterised by 'dirty' guitar, strong riffs and heavy drumming. The 'dirty' sound resulted both from the common use of heavy guitar distortion and feedback, and from a stylistic change in the standard method of playing punk rock. Grunge fuses elements of hardcore punk and heavy metal into a single sound, although sometimes it is performed with more emphasis on one or the other.

Grunge bands were noted for their punk mentality and attitudes and the music shares with punk its raw sound, fast tempos and often vocal delivery. However, grunge also involves slower tempos, dissonant harmonies and more complex instrumentation reminiscent of heavy metal. The lyrics bear similarities to those of punk and concern similar themes such as social alienation, apathy, entrapment and a desire for freedom. They are typically angst-filled and often explore issues such as depression and drug addiction.

Grunge concerts were known for being straightforward, high-energy performances. Grunge bands avoided the complex, high budget presentations that bands from other musical genres such as heavy metal were known for. Instead, the bands presented themselves no differently from any local band. However the concerts did have some level of interactivity with fans and musicians alike participating in stage diving, crowd surfing, headbanging and pogoing, though the audiences at grunge concerts were best known for their extremely enthusiastic moshing. The mosh pits would be located close to the stage, allowing such interaction between the audience and the band.