Friday is Pi Day, a national celebration of the mathematical concept, which is the ratio of a circle's circumference to its diameter and equals 3.14... Schools and museums often plan events to celebrate the concept, which has fascinated humans for centuries, and local eateries offer pie-related deals.

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

Pi Day is Friday, March 14, and several national chains are celebrating with deals and discounts on pie and pizza.

It's National Pi Day, so treat yourself to some pie — pizza, dessert or both, whatever your heart desires! That first "Pi" isn't a typo and differs from the tasty "pie" we eat, though we could easily draw some geometric similarities between the two.

Pi Day is a favorite holiday for both food lovers and mathematicians. For the foodies, the reasoning is simple. Pi Day brings discounts and deals for people looking to grab a pizza to celebrate the holiday.

Pi, defined as the ratio between the circumference of a circle and its diameter, is what's known as an irrational number. Despite its ubiquity, not only across math but also in fields as varied as medicine,

National Pi Day 2025 brings pizza and pie deals nationwide, with discounts like $3.14 pizzas and freebies from major chains.