Tool is an American rock band from Los Angeles, California, formed in 1990. Since their inception, the band's line-up has included drummer Danny Carey, guitarist Adam Jones, and vocalist Maynard James Keenan. Since 1995, Justin Chancellor has been the band's bassist, replacing their original bassist Paul D'Amour. Tool is known to have rigorous touring schedules in support of their albums, they have performed well on charts worldwide, and have sold an estimated 9.25 million records in the United States alone.
Tool emerged with a heavy metal sound on their first studio album Undertow in 1993, at a time when the genre was dominated by thrash metal; and later became a dominant act in the alternative metal movement with the release of their second effort, Ænima, in 1996. Their efforts to unify musical experimentation, visual arts, and a message of personal evolution continued with their third album, Lateralus, in 2001; and their most recent album, 10,000 Days, released in 2006, gained the band critical acclaim and success around the world.
Due to Tool's incorporation of visual arts and relatively long and complex releases, the band is generally described as a style-transcending act and part of progressive rock and art rock. The relationship between the band and today's music industry is ambivalent, at times marked by censorship and the band members' insistence on privacy.