As the voice of Bart Simpson and numerous other characters on The Simpsons, Nancy Cartwright is one of the most famous voice actors on the planet. She's now revealed more insight into how she came up with voice of the bully Nelson Muntz and specifically his iconic "haw-haw" laughing insult.

Nelson made his debut in the Season 1 episode "Bart the General." Cartwright said on Twitter that she was assigned the part of Nelson for the episode and wondered, "Who is he? What does he sound like?" There was no audition process for Nelson--Cartwright had to make it all up on her own.

"All of a sudden, I'm assigned this part. OK, I've got to come up with the sound. So I'm thinking, 'What does a bully sound like?' That's really all I thought of. What does a bully sound like?" she said.