April Fools' Day is celebrated in different countries on April 1 every year. Sometimes referred to as All Fools' Day, April 1 is not a national holiday, but is widely recognized and celebrated as a day when people play practical jokes and hoaxes on each other.

In France and Italy, children and adults traditionally tack paper fish on each other's back as a trick and shout "april fish!" in their local language ("poisson d'avril!" and "pesce d'aprile!" in French and Italian respectively).