Ha Ha!

Ha Ha! (sometimes spelled Haw Haw!) is Nelson's catchphrase and distinctive laugh. Nelson says the laugh with the emphasis on the first "Ha," so it sounds like "HA-ha!"

Nelson usually uses the laugh when something bad happens to another character. Sometimes, after he uses the laugh, he says why he is laughing at the person. For example, he says, "Ha ha! Your dad's not handy!" to Bart after his ten-speed bike (which Homer had assembled) fell apart while Bart was riding it.

Sometimes Nelson laughs for so long at a time that his voice gets really tired and croaky.

Nelson seems to think that using the laugh gets him off the hook if he happens to cause something bad to happen to another person. For example, Nelson pranked Bart into falling out of a tree and used the laugh after Bart hit the ground. It turned out that Bart had broken his leg. When Milhouse pointed out that Bart was really hurt, Nelson protested, "I said 'Ha-ha'!"

Nelson has been known to use his laugh in other media, such as on Facebook and carving it in wooden letters in shop class.

Reversed
When Nelson laughs at Homer while he (Homer) is having a chili-pepper-induced hallucination, Homer hears the laugh with the emphasis reversed: "Ha-HA!"

Four "Ha"s
When Nelson appears as a young, his laugh has four "Ha"s and he sings it so that it sounds like the opening notes of : "Ha-ha-ha-haaaaaaa, ha-ha-ha-haaaaaaa!"

Question
Sometimes Nelson will start the laugh, and then partway through realize that the joke is actually on him, and the laugh comes out sounding like a question: "Ha-HA?"

Battle Cry
Nelson uses his laugh as a battle cry when he helps Bart and Lisa defend their box fort from a horde of American Shipping Services delivery people.

Canadian
The Canadian Nelson says "Hoo Hoo!"

Irish
The Irish Nelson says "Har Har!"

Sign
Bart performed a skateboard trick and wiped out by running full tilt into the side of the school bus. Nelson, who was on the bus, held up a sign in the window reading "HAW HAW!"

See-Saw
When Bart jumps on the see-saw and the trash bag on the other side lands on him, Nelson says "See-Saw!" in the same way as "Ha Ha!".

Facebook
Nelson trips up Facebook founder in a roller-skating rink. Zuckerberg falls and hurts himself and updates his status on Facebook to "is in intense pain". Nelson replies, posting "Haw Haw!"

Uses by Other Characters

 * Mrs. Muntz has been known to use the laugh.
 * Nelson laughed at a tall man driving a Volkswagen. The man got out of his car, confronted Nelson and lectured him. He then turned the tables on Nelson by making him walk down the street with his pants pulled down around his ankles while everyone in Springfield laughed at him.
 * Bart was the only guest to attend Nelson's birthday party. The next day on the school bus, Nelson began treating Bart like his new best friend, much to Bart's discomfiture, and Lisa laughed at Bart.
 * When Springfield Elementary School had a medieval festival, Nelson laughed when Mrs. Krabappel announced that Martin Prince, Jr. would be the king. Mrs. Krabappel, for her part, said that Nelson would be one of the king's guards, and laughed at him when he looked shocked.
 * When Bart had a string of pranks backfire (they ended up helping people instead of causing trouble), Reverend Lovejoy laughed at Bart when he grumbled that every time he tried to do evil, he ended up doing good.