The first day of April is observed as the day for pranks, jokes and deliberate trickery worldwide known as April Fool's day. The day is celebrated with practical jokes on friends, colleagues, family members and neighbours. Fooling each other is just making fun of, and a simple attempt to embarrass others. Traditionally, in some countries, like the UK, Australia, New Zealand, Canada and South Africa, the jokes only last till the noon. Someone who plays a trick after noon is called an "April Fool". Elsewhere like Ireland, France, and America, the jokes last all day.
In 1582, Pope Gregory XIII ordered a new calendar, the Gregorian Calendar, to replace the old Julian Calendar. Pope Gregory XIII introduced the calendar for the Christian world. According to this calendar the new year's day was shifted from 1st April to 1st January. France was the first country to switch from the Julian to the Gregorian calendar in 1582. According to a popular explanation, many people either refused to accept the new date, or did not learn about it, and continued to celebrate New Year's Day on 1st April. Other people began to make fun of these traditionalists, sending them on "fool's errands" or trying to trick them into believing something false. Eventually, the practice spread throughout Europe.
Other sources said that the concept of April Fool's day was provided by Joseph Boskin,a professor of history at Boston University. He explained that the practice of April fool's day came during the reign of Constantine when a group of court jesters and fools told the Roman emperor that they could do a better job of running the empire. Constantine, amused, allowed a jester named Kugel to be king for one day. Kugel passed an edict calling for absurdity on that day, and the custom became an annual event. At that time it was a very serious day. In those times foos were really wise men and it was the role of the Jesters to put things in perspective and humour.
According to an English newspaper article published April 13, 1789, the day had its origin when Noah sent his dove 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, in the Nun's Priest's tale, a tale of two fools, Chanticleer and the fox, which took place on March