Before they were Green Day, Billie Joe Armstrong and Mike Dirnt performed under the name 'Sweet Children.' They changed their name to 'Green Day' shortly before the release of their first EP to avoid confusion with another local California band called 'Sweet Baby.' The name 'Green Day' was a slang term in their hometown of Rodeo, California, for spending a whole day doing nothing but smoking marijuana. Billie Joe Armstrong wrote a song with that title, and the band felt the name suited their stoner-punk aesthetic at the time. Despite their humble beginnings in the Gilman Street punk scene, Green Day became one of the most successful bands of all time, with 'Dookie' and 'American Idiot' becoming multi-platinum masterpieces that redefined punk for a new generation.