The endless number has been useful, puzzling, and an obsession. Not every mathematical constant gets its own day. But not every constant is π. Pi Day got started in 1988 in San Francisco, when Larry Shaw,...

# Happy Pi Day!

For more than 30 years, the world has celebrated the mathematical constant of π, or 3.14159..., on March 14 (get it?). It also happens to be Albert Einstein's birthday. The idea for Pi Day started in 1988 when museum curator Larry Shaw discovered the connection, and so now we celebrate the day every year by eating pies. Read more about Pi Day in this Storyboard.

March 14 isn't just Pi Day. It also has a surprising history of famous births, the death of physicist Stephen Hawking and a milestone for a daring dirigible.

If you're not properly appreciative of pi, NASA is here to help. Pi is the ratio of a circle's circumference to its diameter, a mathematical constant …

It’s Pi Day, the nerdiest of holidays because it’s all about a mathematical constant that represents the ratio of a circle’s circumference to its diameter (yes, sometimes writing majors do pay attention...

Instagram has added a new set of custom stickers to celebrate women in tech, science, engineering and maths as part of Pi Day, which users can add to …

Pi Day isn't just for people who love circles. It's for people who love food in the shape of a circle, too. Published on 3/13/2021 at 6:00 PM Photo …