Ambiguity - A technique that allows one image to be interpreted in more than one way. The ambiguity can be visual, such as an optical illusion, or intellectual, such as an image with two meanings that compete for dominance.

Caricature - A satirical portrait in which the subject's distinctive features or peculiarities are exaggerated or distorted for comic effect; A form of sarcasm that rises from unconcealed snobbery about what is proper or vulgar, in good taste or bad.

Gag - Visual slapstick designed to trigger outright laughter. The word seems to have originated in the world of circus clowns, vaudeville, and silent movies. Gags include pratfalls, funny faces, odd props, and objects popping out of people's heads.

Homage - A visual expression of respect for another work or artist, usually in the form of a spoof. DaVinci's Mona Lisa, and Grant Wood's American Gothic have been favorite targets for graphic homage. The wit lies in choosing a work with particular relevance to the client's message and audience.

Irony - A visual or verbal expression that conveys the opposite of its literal meaning, with the result of intensifying meaning. An example is Steven Doyle's design for the first in a series of Kromekote brochures; large type on the cover proclaims "The End."

Parody - A design that braodly mimics the characteristic style of a well known work or institution and holds it up to ridicule. A take-off, or spoof, such as the magazine-in-sheep's-clothing Is Martha Stewart Living?

Rebus - A visual riddle in which words or letters represented by images or symbols. The image can be used to either represent the sound or the meaning of the word. A classic example is a Paul Rand poster with the letters IBM, in which the "I" is represented by the human eye, and the "B" is represented by a bumblebee.

Self-depracating humor - Humor in which the client or the product is the butt of the joke. Self-depracation can be a highly effective way to disarm suspicion or reverse negative perceptions. A famous example of this technique was the successful Volkswagon campaign of the '60s, which poked fun at the product's ugliness, referring to it as a "bug."

Tromp l'oeil- An image rendered in fine detail to fool the viewer into thinking an abject is real. From the French, meaning "trick the eye."

Visual pun - Like a verbal pun, which is a play on words, a visual pun is a play on pictures--two strings of thought tied together with a visual knot. Verbal and visual puns are the most frequently attempted form of wit, and often the most banal. Said Oscar Levant: "A pun is the lowest form of humor--when you didn't think of it yourself.

Wit - A smart form of humor that reveals similarities between things thought to be different, or differences between things thought to be similar. Unlike broader forms of humor, such as gags, puns and parodies, graphic wit combines a visual twist with a sage observation.