April Fool's Day is celebrated annually on April 1st. It is a day where people play practical jokes and hoaxes on each other. The origins of the tradition are unclear. Around the world, different cultures have their own April Fool's Day traditions, such as in Poland where people play jokes by pouring water on each other. Practical jokes are playful tricks intended to amuse that often embarrass the recipient. Those who believe the jokes easily are considered gullible.