Math geeks and students celebrate Pi Day every March 14 . Pi , or roughly 3.14 , is the ratio of area to diameter of a circle . Across the country , math geeks in museums , schools , private groups and elsewhere gather to celebrate the number pi , approximately 3.14 . The Pi Day holiday was started at the Oakland Museum in San Francisco . Albert Einstein was also born on March 14 .
Math geeks and students celebrate Pi Day every March 14 . Pi , or roughly 3.14 , is the ratio of area to diameter of a circle . The Pi Day holiday was started at the Oakland Museum in San Francisco . Albert Einstein was also born on March 14 .