April Fools' Day (рус .День смеха) is a non-official holiday celebrated in Russia, Ukraine, Belarus and some other countries on April 1. Traditionally jokes are played on family members, friends, co-workers, neighbours on this day. Hoaxes and sending someone on fool's errands are most popular and usually work if a person has forgotten about the date.

The first April day trick was played in Russia in Moscow in 1703. Town criers were wondering the city and inviting everyone to come and see the unprecedented performance. Huge masses of people gathered to watch it and when finally the curtains were drawn, people just saw as stretched canvas with the words : "Do not believe anyone on April 1". And no performance actually took place.

Speaking about April 1 we often recall the annual Humoryna festival (festival of humor) carried out on and around the April Fool's Day in Odessa, Ukraine. Unlike other countries and cities April 1 is an official day off in Odessa and a merry feast including tricks, shows, concerts and fireworks. The culmination of the celebration is Odessa carnival held on Sobornaya square.