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April Fools' Day, also known as All Fools' Day, is celebrated on the 1st of April every year. It is a day when people play practical jokes and hoaxes on each other, often with the aim of making others believe something that is not true. This tradition is observed in many countries around the world, and it is a day filled with laughter and fun.

The origins of April Fools' Day are not entirely clear, but it is believed to have started in Europe during the late Middle Ages. Some historians suggest that it may have been influenced by ancient Roman festivals such as Hilaria, which were celebrated in late March. Others believe that it may have originated from the change of the calendar in the 16th century, when the Julian calendar was replaced by the Gregorian calendar.