A joke is a short story or ironic depiction of a situation communicated with the intent of being humorous. It can also be used a slang term for a person who is not taken seriously by others in general or is known as being a failure. A practical joke or prank differs from a spoken one in that the major component of the humor is physical rather than verbal (for example placing salt in the sugar bowl).
Jokes are typically for the entertainment of friends and onlookers. The desired response is generally laughter; when this does not happen the joke is said to have "fallen flat".