I'm not much of a fan of the "knock knock" jokes........
"yo mamma" jokes can be funny at times
and I like "that's what she said" jokes... and I love The Office... lol
yo mamma AND thats what she said. they are both SO stupid, that whenever i hear them, i laugh. cuz its so over done, and old its so stupid that the person saying them think it is actually funny . in fact, it was never funny.