Nirvana was an American grunge band formed in 1987 that achieved worldwide fame in the early 1990s. The band consisted of Kurt Cobain (vocals, guitar), Krist Novoselic (bass), and Dave Grohl (drums). They released their breakthrough album Nevermind in 1991, which sold over 30 million copies worldwide and featured their hit single "Smells Like Teen Spirit". However, the band struggled with the pressures of fame and Kurt Cobain's heroin addiction. Cobain died by suicide in 1994 at the age of 27.