Green Day is an American punk rock trio formed in 1987. The band has consisted of lead vocalist and guitarist Billie Joe Armstrong, bassist and backing vocalist Mike Dirnt, and drummer Tré Cool for the majority of its existence. The band is credited as one of the three main bands, along with The Offspring and Rancid, who put the punk revival into process. Green Day was originally part of the punk scene at 924 Gilman Street in Berkeley, California. The band's early releases for independent record label Lookout! Records earned it a grassroots fanbase. Nevertheless, its major label debut Dookie (1994) became a breakout success and eventually sold over 10 million copies in the U.S. and 15 million worldwide. As a result, Green Day was widely credited, alongside fellow California punk bands The Offspring and Rancid, with reviving mainstream interest in and popularizing punk rock in the United States. Green Day's three follow-up albums, Insomniac, Nimrod and Warning did not achieve the massive success of Dookie, but they were still successful, reaching double platinum, double platinum, and gold status respectively. Green Day's 2004 American Idiot reignited the band's popularity with a younger generation, selling five million copies in the U.S. The band's eighth studio album, 21st Century Breakdown, was released on May 15, 2009. Green Day has sold over 22 million records in the United States. They have won four Grammy Awards : Best Alternative Album for Dookie,Best Rock Album for American Idiot, Record of the Year for "Boulevard of Broken Dreams", and Best Rock Album for the second time for 21st Century Breakdown.