The origin of April Fools' Day is obscure. One likely theory is that the modern holiday was first celebrated soon after the adoption of the Gregorian Calendar; the term referred to someone still adhering to the Julian Calendar which it replaced.In many pre-Christian cultures May Day (May 1) was celebrated as the first day of summer, and signalled the start of the spring planting season. An April Fool was someone who did this prematurely. Another origin is that April 1 was counted the first day of the year in France. When King Charles IX changed that to January 1, some people stayed with April 1. Those who did were called "April Fools" and were taunted by their neighbors.In the eighteenth century the festival was often posited as going back to the times of Noah. An English newspaper article published on April 13th, 1789 said that the day had its origins when he sent the raven off too early, before the waters had receded. He did this on the first day of the Hebrew month that corresponds with April.A possible reference to April Fools' Day can be seen in the Canterbury Tales (ca 1400) in the Nun's Priest's tale, a tale of two fools: Chanticleer and the fox, which took place on March 32nd.
- Left Handed Whoppers: In 1998, Burger King ran an ad in USA Today, saying that people could get a Whopper for left-handed people whose condiments were designed to drip out of the right side.Not only did customers order the new burgers, but some specifically requested the "old", right-handed burger.
- Phone call: In 1998, UK presenter Nic Tuff of West Midlands radio station Kix 96 pretended to be the British Prime Minister Tony Blair when he called the then South African President Nelson Mandela for a chat. It was only at the end of the call when Nic asked Nelson what he was doing for April Fools' Day that the line went dead.
- Spaghetti trees: The BBC television programme Panorama ran a famous hoax in 1957, showing the Swiss harvesting spaghetti from trees. They had claimed that the despised pest, the spaghetti weevil, had been eradicated. A large number of people contacted the BBC wanting to know how to cultivate their own spaghetti trees. It was, in fact, filmed in St Albans.
- Water on Mars: In 2005 a news story was posted on the official NASA website purporting to have pictures of water on Mars. The picture actually was just a picture of a glass of water on a Mars Candy Bar.
But there are real news n April Fool's Day too that somebody might not believe what's happening around them...
- The April 1, 1946 Aleutian Island earthquake tsunami that killed 165 people in Hawaii and Alaska resulted in the creation of a tsunami warning system (specifically the Pacific Tsunami Warning Centre), established in 1949 for Pacific Ocean countries. The tsunami in question is known in Hawaii as the "April Fools' Day Tsunami" due to people drowning because of the assumptions that the warnings were an April Fools' prank.(well i think this is stupid!!)
- The game Mario & Sonic at the Olympic Games was announced only a couple days before April Fools' Day. Forums were flooded because so many thought that the two rivals since the 90's, Mario and Sonic the Hedgehog, appearing together in a video game as an official 2008 Olympics game was a joke.
Well i think whatever it is ,there are things we should take it seriously...