Grunge (sometimes referred to as the Seattle sound) is an alternative rock genre and subculture that emerged during the mid-1980s in the American Pacific Northwest state of Washington, particularly in Seattle and nearby towns. Grunge fuses elements of punk rock and heavy metal, but without punk's structure and speed. The genre featured the distorted electric guitar sound used in both genres, although some bands performed with more emphasis on one or the other. Like these genres, grunge typically uses electric guitar, bass guitar, drums and vocals. Grunge also incorporates influences from indie rock bands such as Sonic Youth. Lyrics are typically angst-filled and introspective, often addressing themes such as social alienation, self-doubt, abuse, neglect, betrayal, social and emotional isolation, addiction, psychological trauma and a desire for freedom. The early grunge movement revolved around Seattle's independent record label Sub Pop and the region's underground music scene. The owners of Sub Pop marketed the style shrewdly, encouraging the media to describe it as "grunge"; the style became known as a hybrid of punk and metal.By the early 1990s, its popularity had spread, with grunge bands appearing in California, then emerging in other parts of the United States and in Australia, building strong followings and signing major record deals. Grunge was commercially successful in the early-to-mid-1990s due to releases such as Nirvana's Nevermind, Pearl Jam's Ten, Soundgarden's Superunknown, 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 of rock music at the time.