ISLAMABAD (APP) April Fools Day is here so be on your toes and mentally alert for unforeseen pranks, practical jokes and other forms of mischief. Some people love to spend days thinking up gags to pull on their friends and family, while others love a little imprompt prank here and there. On the day, most people, especially youngsters, make fun of others by telling fake stories and hitting them with practical jokes. The day has assumed the shape of the 'funniest day of the year in some countries, as people send greetings, jokes and exchange funny SMSs to their friends as well as family members. The history of April Fools Day or All Fools Day is uncertain, but the current thinking is that it began around 1582 in France with the reform of the calendar under Charles IX. The Gregorian Calendar was ntroduced, and New Years Day was moved from March 25 - April 1 (new years week) to Jan 1. Communication travelled slowly in those days and some people were only informed of the change several years later. Still others, who were more rebellious refused to acknowledge the change and continued to celebrate on the last day of the former celebration, April 1. These people were labelled fools by the general populace, were subject to ridicule and sent on fool errands, sent invitations to nonexistent parties and had other practical jokes played upon them. The butts of these pranks became known as a poisson davril or April fish because a young naive fish is easily caught. In addition, one common practice was to hook a paper fish on the back of someone as a joke. This harassment evolved over time and a custom of prank-playing continue on the first day of April. This tradition eventually spread elsewhere like to Britain and Scotland in the 18th century and was introduced to the American colonies by the English and the French. Because of this spread to other countries, April Fools Day has taken on an international flavor with each country celebrating the holiday in its own way. So, no matter where you happen to be in the world on April 1, dont be surprised if April fools fall playfully upon you.