National Pi Day is recognized today in the U.S. and around the world. Here's what to know about the quirky holiday, and how to celebrate.

National Pi Day is recognized today in the U.S. and around the world. Here's what to know about the quirky holiday, and how to celebrate.

SCIENCE Pi Day: what is it and why is it celebrated on 14 March? We’ve done full circle as this special day in the calendar comes around again, one where we celebrate a rather important number.

Pi Day: "Probably no symbol in mathematics has evoked as much mystery, romanticism, misconception and human interest as the number pi," an author once said. Learn more about the famous constant.

Pi Day is the annual celebration of the mathematical constant, Pi. Here's what to know about its date, and why we celebrate it by eating pie.