Tool was formed in 1990 by LA natives Danny Carey, Maynard James Keenan, Adam Jones, and later joined by Justin Chancellor. The band's first release, an EP entitled Opiate, quickly generated buzz in the rock world. Its raw, brutal sound and complex instrumentation were unlike anything in the scene at the time. In 1993 Tool were selected as one of the headliners on the second stage of Lollapalooza. This along with the release of future double-platinum debut album Undertow rocketed them to the forefront of hard rock music.
1996's ?nima would cement Tool's popularity. With a video MTV didn't want to touch, and a single that was still questionable even with radio edits, Tool built their fanbase through word-of-mouth and a powerful live show. The album would go on to win a Grammy for title track "?nima", inspired by comedian Bill Hicks. They headlined Lollapalooza the following year and became dormant for five years.
Tool's return was a powerful one. Their third album Lateralus in 2001 combined the rawness of earlier recordings with their unique guitar stylings, and many more melodic elements than previous outings. After a round of sold-out tours, Keenan left to tour with A Perfect Circle.
Rumors started to fly in 2005 of a possible new tool album. Nothing was confirmed until early 2006 when a distinctly "Tool" album leaked on the internet. 10,000 Days was released on May 2nd to massive popular acclaim. Taking cues from tourmates Fantomas and Meshuggah, Days is equal parts pummeling metal riffs, frantic guitar work, and dissonant ambiance. Lead single "Vicarious" dominated modern rock radio for most of the spring and early summer.