A band that got together in 1988 in California. They were first known as Sweet Children. Their name Green Day was used as a codename for when they were going o smoke marijuwana hence GREEN DAY (second definiton)In 1994, they became famous for their album Dookie and pretty famous for their epic mud war at a live concert. They progressed to a few different styles as shown in Good Riddance(Time of Your Life) and their more recent album 21st Century Breakdown. Even though their style has changed,
Billie Joe Armstrong explains this as a way to connect to more fans and a way to experiment with different genres that he is interested in. They became more widely known for their album,
American Idiot, which was a turning piont for their career as the band put it, after their masters for a different idea were stolen. After fooling around and realizing that they had more fun and got more emotion out of the new ideas, they changed their style to what they believed was better.
Billie Joe Armstrong is also known for the band, Pinhead Gunpowder in 1993 (I believe) and Dirnt, Cool and Armstrong composed another band, Foxburrow Hottubs that came out in 2007, which wasn't quite that succesful. Also, The Network. All of the members are bisexual and have no regrets what so ever.