It means it makes you laugh at your own jokes.
Boy: What did the dog say to the camel?
Girl: What?
Boy: rough!
Boys mind: What do you think of that mr person number 2?
mr person number 2: aaah oooh eeee aaah
Boy: HAHAHAHAHHAHAHA
Girl: Thats not funny.

by 7778 April 29, 2008
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