How America Celebrates Pi Day

Across the country, math geeks in museums, schools, private groups and elsewhere gather to celebrate the number pi, approximately 3.14. That's why March 14 -- 3-14 -- is Pi Day. What's more, Albert Einstein was born on this day.

Throughout history, people have been captivated by this number because there is no way to calculate it exactly by a simple division on your calculator. What's more, its digits go on infinitely, without any pattern in the numbers. 3.1415926535897932 ... etc. Even that many digits are more than most people would need for everyday use, but some folks have been inspired to memorize thousands of digits of pi, or even use the digits to create poetry or music.

If you want to go where the day is said to be "invented," look no further than San Francisco's Exploratorium. Larry Shaw, who worked in the electronics group at the museum, began the tradition in 1988. Last year was Pi Day's 25th anniversary there.