Circles can be found everywhere in the natural world, but with no accurate way to meas.ure them they are very mysterious and might never be fully understood. When you take the distance around a circle and divide it by the distance across a circle, you will always get Pi(m). While Pi is equal to about 3.14 when rounded, it is infinitely long. With the help of computers, mathematicians have been able to calculate Pi out to over a trillion decimal(小数)places. This makes Pi puzzling, even to the most famous mathematicians.

Pi Day is celebrated globally on March 14, since the way we write this date, 3/14, looks just like Pi when rounded. In 2009. U. S. Congress voted to officially make March 14 Pi Day.Certain parts of the world——places where March 14 is written as 14/3—will instead celebrate Pi Approximation Day which takes place on July 22nd because of the result of 22/7.

Pi has appeared in movies, comics, music, and more. "In modern movies, any time the filmmaker wants to create a sense of mystery, the symbol Pi is used,"says Blatner, People also love working to memorize the digits(数位) of Pi and competing against others to see who can remember most. The Guinness World Record for reciting the most digits of PV is held by Lu Chao of China, who successfully recited Pi to nearly 67.000 decimal places.

Above all, Pi Day is about having fun with the number, according to Blatner. People will celebrate Pi Day by eating pie and throwing pie, and with fun Pi-related games. Princeton,New Jersey holds a series of Pi-related festivities. Events this year include a surprise birthday party for Albert Einstein whose birthday also falls on March 14, and a "Walk a Pi Event"where participants will walk 3.14 miles together. Just like the number itself, the possibilities for Pi Day are truly endless.