Green Day is an American punk rock band formed in 1987 in East Bay, California. The group consists of lead vocalist and guitarist Billie Joe Armstrong, bassist and backing vocalist Mike Dirnt, and drummer Tré Cool. They achieved mainstream success with their third studio album, Dookie (1994), which sold over 10 million copies in the United States and won a Grammy Award for Best Alternative Album. The album's high-energy tracks and rebellious lyrics, exemplified by hits like "Basket Case" and "When I Come Around," helped bring punk rock into the mainstream and defined a generation.

Over the years, Green Day has continued to evolve their sound and maintain their relevance in the music industry. Their critically acclaimed albums Insomniac (1995), Nimrod (1997), and Warning (2000) showcased their ability to blend punk rock with other musical styles. In 2004, they released American Idiot, a rock opera that provided a scathing critique of American society and politics. The album was a commercial success, earning them another Grammy Award and spawning the hit singles "Boulevard of Broken Dreams" and "Wake Me Up When September Ends."

Green Day's impact extends beyond their music. They have been vocal advocates for various social and political causes, often using their platform to promote activism and change. Their energetic live performances and ability to connect with fans have solidified their status as punk rock legends. As they continue to release new music and tour, Green Day remains a vital and influential force in the music world, inspiring countless bands and fans with their relentless spirit and uncompromising vision.