Nelson Muntz is the bully on The Simpsons and is voiced by Nancy Cartwright.  Nelson is probably best known for his class "Hah Hah" laugh he does at everyone.

Though Nelson is typically foun bullying Bart and other students, we've also seen his softer side as Lisa's boyfriend and even as Bart's friend.

Nelson Muntz Quotes

I like to cry at the ocean, because only there do my tears seem small.

</i> Nelson

Bart: Boys and girls, Mrs. Krabappel, I come before you today to solve a riddle that has plagued mankind for centuries: What has four legs and ticks?
Milhouse: A walking clock?
Nelson: A walking clock!
Martin: I'd wager he has some variety of walking clock in that box!
Edna: Bart, is it a walking clock?
Bart: What?.....No, it's my dog.

The Simpsons Quotes

Homer: (Wearing glasses) The sum of the square roots of any two sides of an isosceles triangle is equal to the square root of the remaining side!
Man: (From inside a bathroom stall.) That's a right triangle, you idiot!
Homer: D'oh!

Son, a woman is a lot like a... a refrigerator! They're about six feet tall, 300 pounds. They make ice, and um Oh, wait a minute! Actually, a woman is more like a beer. They smell good, they look good, you'd step over your own mother just to get one! But you can't stop at one, you wanna drink another woman!

Homer