Happy Birthday Michael Ryan Pritchard! (born May 4, 1972), known professionally as Mike Dirnt, is an American musician, songwriter and composer. He is best known as the co-founder, bassist, backing vocalist and occasional lead vocalist of American punk rock band Green Day. He has also played in several other bands, including The Frustrators. His stage name was originally a nickname from his friends at grade school, as he would constantly play “air bass” and make a “dirnt, dirnt, dirnt” noise while pretending to pluck the strings.
More about Mike Dirnt here.