Learn these interesting facts about pi before Pi Day on March 14 Facts about pi you don’t want to miss How much do you really know about pi? Sure, you’ve heard about it in math class—potentially sharing a pi joke or two— but this famous number has a history so fascinating that it even has its own holiday.

Pi, which is the ratio of a circle's circumference to its diameter, is celebrated with its own holiday on March 14.

Pi Day itself dates to 1988, when physicist Larry Shaw began celebrations at the Exploratorium science museum in San Francisco. The holiday didn’t really gain national recogniti