What is April Fool's Day and what are its origins? It is commonly believed that in medieval France, New Year was celebrated on 1 April. Then in 1562, Pope Gregory introduced a new calendar for the Christian world, changing New Year to 1 January. With no modern communications, news travelled slowly and new ideas were often questioned. Many people did not hear of the change, others chose to ignore it, while some merely forgot. These people were called fools. Invitations to non-existent New Year parties were sent and other practical jokes were played. This jesting evolved over time into a tradition of playing pranks on 1 April. The custom eventually spread to England and Scotland, and it was later transported across the Atlantic to the American colonies of the English and the French. April Fools Day has now developed into an international festival of fun, with different nationalities celebrating the day in special ways. In France and Italy, if someone plays a trick on you, you are the fish of April. By the month of April fish have only just hatched and are therefore easy to catch. Children stick paper fish to their friends' backs and chocolate fish are found in the shops. In Scotland, April Fools Day lasts for two days! The second day is called Taily Day and tricks on this day involve the bottom or the tail in informal speech. Often a sign saying kick me is stuck onto someone's back without them knowing. In Spain and Mexico, similar celebrations take place on 28 December. The day is the Feast of the Holy Innocents. Originally, the day was a sad remembrance of the slaughter of the innocent children by Herod in his search for the baby Jesus. It eventually changed to a lighter commemoration of innocence involving pranks and trickery. Today, Americans and the British play small tricks on friends and strangers alike on 1 April. A common trick is to point to a friend's shoe and say Your shoelace is untied. When they look down, they are laughed at. Schoolchildren might tell a friend that school has been cancelled. A bag of flour might be balanced on the top of a door so that when the victim opens the door, the flour empties over their head. Sometimes the media gets involved. Once, a British short film was shown on April Fools Day about spaghetti farmers and how they harvest their crop from spaghetti trees! Most April Fool jokes are in good fun and not meant to harm anyone. The best trick is the one where everyone laughs, especially the person upon whom the joke has been played. Two British policemen were sent to investigate a glowing flying saucer on 31 March, the day before April Fool's Day. When the policemen arrived at a field in Surrey, they saw a small figure wearing a silver space suit walking out of a spacecraft. Immediately the police ran off in the opposite direction. Reports revealed that the alien was in fact a midget, and the flying saucer was a hot air balloon that had been specially built to look like a UFO by Richard Branson, the 36-year-old chairman of Virgin Records. Branson had planned to land the balloon in London's Hyde Park on 1 April. However, a wind change had brought him down in a Surrey field. The police were bombarded with phone calls from terrified motorists as the balloon drifted over the motorway. One lady was so shocked by the incident that she didn't realise that she was standing naked in front of her window as she was describing the UFO to a radio station.