|A hoax in Copenhaguen - "Aprilsnar 2001" by Lars Andersen|
Licensed under Public Domain via Wikimedia Commons
All Fools' Day or April Fools' Day is celebrated every year on the 1st of April. This celebration is similar to the Spanish one, Día de los Santos Inocentes, celebrated on the 28th of December.
People typically play practical jokes and hoaxes on each other. The jokes and their victims are known as "April fools". Hoax stories may be reported by the press and other media on this day and explained on subsequent days. Popular since the 19th century, the day is not a national holiday in any country, but it is well known in India, Canada, Europe, Australia, Brazil and the United States.
The earliest recorded association between 1 April and foolishness can be found in Geoffrey Chaucer's The Canterbury Tales (1392). Some writers suggest that the restoration of 1 January as New Year's Day in the 16th century was responsible for the creation of the holiday, but this theory does not explain earlier references.
Read more at http://en.wikipedia.org/wiki/April_Fools%27_Day