Nancy Campbell Cartwright (born October 25, 1957) is an American actress and voice actress. She is best known for her long-running role as Bart Simpson on the animated television series The Simpsons. Cartwright voices other characters for the show, including Nelson Muntz, Ralph Wiggum, Todd Flanders, Kearney and Database.
For Nickelodeon, she voiced the Junk Food Kid in the 1992 Rugrats episode "Showdown at Teeter-Totter Gulch". Ten years later, she would replace the retired Christine Cavanaugh as the voice of Chuckie Finster until the end of the series, a role she would reprise in the 2003 movie Rugrats Go Wild and the spinoff All Grown Up!. She was also the voice of Chum Chum in the original Random! Cartoons short "Fanboy". When the series started production, the role was given to Nika Futterman.