Jokes that include a reference to fungi often employ the use of a pun to create a humorous twist. An example from Comedy Central's website is, "A mushroom goes into a bar and sits down to order a drink. The bartender walks over and says 'I'm sorry sir, but we don't serve your kind here.' The mushroom sits back and asks, 'Why not? I'm a fun guy (fungi)!'"
A mushroom is one of the most commonly recognizable forms of fungi, and the words "fun guy," sound almost precisely the same as "fungi" when spoken aloud. Numerous other jokes can be created utilizing this pun, which plays on the interchange of "fungi" and "fun guy." For example, Question: "Why is the mushroom always invited to parties?" Answer: "Because he's a fun guy."
The use of such puns is most common in question-and-answer jokes. Puns are often used in riddle jokes, in which a straight answer is expected in response to a common riddle question. Following the question, the answer is unexpectedly twisted with a pun or other comic technique, such as a spoonerism, to create a humorous effect. Such types of riddle jokes include "knock-knock" jokes, "chicken crossing the road" jokes, and "light-bulb" jokes, as well as the "what's the difference between" jokes.