Guide Note: April Fools' Day is celebrated on the first day of April each year and is usually marked by the playing of jokes, pranks and elaborate hoaxes. While the exact origins of the day remain unclear, the most common historical interpretation dates back to 16th century France.

Up until that point, New Year's Day had been celebrated on the 1st of April each year. In 1564 (with the introduction of the Gregorian calender), Charles IX of France decreed that New Year's Day would be moved to the 1st of January - as it is today. Due to the slow pace that news traveled in those days, many people didn't hear about the change and continued celebrating the New Year on April 1st. Those who had heard about the news began playing jokes and pranks on those that hadn't, such as inviting them to fake New Year's parties and sending them foolish gifts. Thus the tradition of April Fools' Day began. Fast Facts:

1. Celebrated on April 1st
2. Also known as All Fools' Day
3. Not an actual holiday
4. Named after the 1984 horror movie classic April Fool's Day
5. It is a custom to try to send someone on a Fool's Errand
6. French children have a tradition of taping a picture of a fish (also known as a Poisson d'Avril) to their schoolmate's backs
7. Mr. T pities the April Fool
8. The birthday of Fred and George Weasley from the Harry Potter series
9. "This is the day upon which we are reminded of what we are on the other three-hundred and sixty-four." — Mark Twain
10. Belguins do not celebrate April Fools' Day because they do not have a sense of humor