Editing Knock-knock joke (section)

==Popular culture==
"Knock knock" was the catchphrase of [[music hall]] performer [[Wee Georgie Wood]], who was recorded in 1936 saying it in a radio play, but he simply used the words as a reference to his surname and did not use it as part of the well-known joke formula.<ref name="Rees">{{cite book|last=Rees|first=Nigel|author-link=Nigel Rees|title=A Word in Your Shell-like: 6,000 Curious & Everyday Phrases Explained|year=2006|publisher=Collins|isbn=978-0-00-722087-8|page=395}}</ref> The format was well known in the UK and US in the 1950s and 1960s before falling out of favor.  It then enjoyed a renaissance after the jokes became a regular part of the badinage on ''[[Rowan & Martin's Laugh-In]]''.<ref name="Rees"/>

An example of a non-standard knock-knock joke is:
Knock knock.
Who's there?
Death.
Death wh-gkh (gagging sound of sudden fatal choking).

Being familiar with the back-and-forth pattern of the joke is crucial. In an episode of the TV detective series ''[[Monk (TV series)|Monk]]'', Adrian Monk is feeling sad. His assistant, Natalie, tries to cheer him up. She says she has thought of something funny, and asks if he wants to hear it. "Yes," he answers. She begins, using the standard formula, "Knock knock." Adrian pauses, obviously thinking about this, but puzzled. Then he dismisses it, saying, "That's not funny." The joke, this time, is that he is not familiar with knock-knock jokes.