I'm told the oldest known joke in the world originates in the olden days of Greeks and that.
A man goes to the barbers, and the barber says "How would you like your hair cut?" To which the man responds "In silence". What larks.

Of course, the oldest joke in the world is probably when the first caveman farted in the other caveman's face.
(rnuk http://flickr.com/rnuk, Mon 13 Aug 2007, 12:05, archived)

Or scrawled a crude cock onto somebody's carefully crafted picture of a mammoth.

( Dr. Shambolic je suis charlie, Mon 13 Aug 2007, 12:06, archived)

Somebody only moaned underneath it that the original picture was too big.

( FoldsFive, Mon 13 Aug 2007, 12:12, archived)