Pi Day is an annual celebration commemorating the mathematical constant π (the Greek letter pi), the symbol for the ratio of the circumference of a circle to its diameter. Pi Day is celebrated around the world on March 14th since Pi = 3.1415926535…
Next year will be especially exciting: in the year 2015, Pi Day will have special significance at 9:26:53 a.m. and p.m., with the date and time representing the first 10 digits of pi.
While the American Pie Council (APC) denotes January 23 as National PIE Day, the U.S. Congress recognizes March 14 as PI Day, but both can be celebrated by baking pies.
According to the APC, the first pies were probably made by early Romans, and appeared in England as early as the Twelfth Century. Pie came to America with the first English settlers. The early colonists cooked their pies in long narrow pans calling them “coffins” like the crust was called in England. Among the other benefits of the American Revolution, it brought into common use the word “crust” rather than “coffin.”
How to celebrate? Make your pie big enough to share! “Hand pies” may not be appropriate, as shown by this calculation by Trader Joe’s:
On the other hand, this “pi pie,” created at Delft University of Technology in 2008 suggests a more share-friendly approach to Pi Day!