Sight gag

In comedy, a visual gag or sight gag is anything which conveys its humour visually, often without words being used at all. The gag may involve a physical impossibility or an unexpected occurrence. The humor is caused by alternative interpretations of the goings-on. Visual gags are used in magic, plays, and acting on television / movies.

The most common type of visual gag is based on multiple interpretations of a series of events. This type is used in the 1935 Alfred Hitchcock film The 39 Steps. Lead actor Robert Donat was kidnapping actress Madeleine Carroll and they were handcuffed. When they checked into an inn, the innkeeper assumed that they were passionate lovers because of the handcuffs. The film used dialogue that could be interpreted both ways.

Another visual gag is a switched image, often at the beginning of a film. A subsequent view of the scene shows something not viewed before. Switched movement may be the gag, such as Charlie Chaplin in The Pawnshop. Chaplin fights with his coworker and punches at him once. Their boss walks in mid-swing and Chaplin changes the motion to act like he was dropping to his knees to scrub the floor.

Noel Carroll established the most influential taxonomy of sight gags, breaking down the varieties into six types, two of which are enumerated below.

Mutual Interference: The audience is fully aware of the on-screen situation, but a character comically misunderstands

Mimed Metaphor: A variety of virtual simile an object may be treated as if it is a different object or be used in an unconventional way, such as acting like a doughnut is a barbell or using a tuba as an umbrella holder.

There are numerous examples in cinema history of directors who based most of the humor in their films on visual gags, even to the point of using no or minimal dialogue. Visual gags began in live theater. The first known use of a visual gag in a film was in the Lumière brothers' 1895 short, L'Arroseur Arrosé ("The Waterer Watered"), in which a gardener watering his plants becomes the subject of a boy's prank. An early pioneer in visual gags was Georges Méliès. The filmmaker experimented with techniques in the then-new film media creating techniques to trick viewers.

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