how did april fools’ day become a thing?

April Fools' Day is tomorrow, which means we're all going to be sleeping with one eye open and inspecting our chairs before sitting down. But in these final hours before it's socially acceptable to be kind of a jerk to your friends, let's take a moment to reflect. Who started this day of fooling, and why? The history of the weird holiday, in 60 seconds, above.