Nancy Jean Cartwright (born on October 25, 1957 in Dayton, Ohio) is an American actress, voice actress, comedian, clown, jester, mime and tap dancer. She is known for providing the voices of Bart Simpson, Nelson Muntz, Todd Flanders and Ralph Wiggum on the animated television show The Simpsons. She also plays the voice of Chuckie Finster on Rugrats and All Grown Up!.
Cartwright graduated from Fairmont High School. She went to Ohio University and the University of Los Angeles (UCLA). At UCLA, she earned a degree in theatre.