Maybe today you will be the victim of a practical joke. For centuries, April 1 has been a day marked by hoaxes and practical jokes played on people around the world. If you fall for one of these pranks, then you are an April fool.
This tradition goes back to Europe in the mid-1600s, and crossed over to the English-speaking world in the late seventeenth century.
Although the origins of April Fools is still debatable, most references trace it back to France and the French calendar reform of the sixteenth century.
Those who did not accept the change became the focus of April jokes and were mocked as fools. Pranks were played on, like being invited to parties that never occurred. In rural areas, word of the change was not always known, so these people were also mocked for celebrating the new year on the wrong day.
The tradition of pranking these "fools" commonly included sneaking a paper fish to their backs. These victims were called Poisson d’Avril, or April Fish. Today the term is still used in France for April Fools where the tradition is more popular with younger children. Bakeries and cholocatiers even make fish-shaped treats for the "holiday."
Why related to fish? That's unclear but it has been suggested that it relates to the zodiac sign of Pisces (a fish), which falls near April.
In Italy, Il Pesce d’Aprile, or April’s Fish, is very similar. Youngsters secretly attach a paper cutout pesciolino (small fish) to the back a school companion and then everyone asks, "L’hai visto?—Chi?—Il pesce d’Aprile!" (or Have you seen?—Who?—the April Fool!) and laugh ay the Fool.
In France, Italy and other countries adults get in on the game, usually minus the fish.