This year, though, it comes with some twists that won’t be seen again for a century. Pi Day, celebrated on March 14 (3/14), honors the number π (approximately 3.14), which represents the ratio of a circle’s circumference to its diameter.

Not matter how you slice it, March 14 has something for everyone. The national holiday has been celebrated for decades now, since the late 1980s, thanks to a San Francisco physicist. Larry Shaw, also known as the “Prince of Pi,

On March 14, math classes across the country will celebrate Pi Day—a national holiday in honor of the mathematical constant pi, which represents the ratio of a circle’s circumference to its diameter and starts with the digits 3.

Pi Day is celebrated annually on March 14, because its numerical date aligns with the first three digits of the mathematical constant π, 3.14. And in some places, particularly Massachusetts colleges,