Believe it or not, April Fool's Day might date back to ancient Roman and Celtic festivals, where people would celebrate the arrival of spring with light-hearted pranks and mischief.
In 1582, France switched from the Julian calendar to the Gregorian calendar, and with this, New Year's Day moved from April 1st to January 1st. Apparently, some people continued to celebrate New Year's on April 1st, and they were labelled "April fools".
April Fool's Day is celebrated in various forms around the world. In France, it is known as "Poisson d'Avril" (April Fish), and people tape paper fish to each other's backs as a prank. In Scotland, it is a two-day event known as "Hunt the Gowk," where people send others on fruitless errands.
Over the years, media outlets have often participated in the pranking. In 1957, the BBC broadcast a fake documentary about spaghetti crops in Switzerland, successfully fooling many viewers into calling to inquire about how to grow spaghetti trees.