Kurt Donald Cobain ( February 20 , 1967 - c. April 5 , 1994 ) was the lead singer and guitarist of the grunge band Nirvana , which also included bassist Krist Novoselic and drummer Dave Grohl . Kurt Donald Cobain ( February 20 , 1967 â `` c. April 5 , 1994 ) was an American singer-songwriter , musician and artist , best known as the lead singer and guitarist of the grunge band Nirvana .