March 14, written as 3-14 in the United States date format, represents the common three-digit approximation for the number π: 3.14. It is often celebrated at 1:59 p.m. in recognition of the six-digit approximation: 3.14159. Some, using a 24-hour clock, celebrate it at 1:59 a.m. or 3:09 p.m. (15:09) instead.

Pi Day is celebrated in a variety of ways. Parties or other observances may be held by mathematics departments in educational institutions. Math or science clubs might gather to consider the role that the number π has played in their lives and to imagine the world without π. During such an event, pi celebrants may devise alternative values for π, eat pie, play piñata, drink Piña Colada, eat pineapple, listen to the song "Pi" by Kate Bush, or watch Pi. The shape of the pie is sometimes square, due to the pronunciation of the equation for the surface area bounded by a circle = πr2, i.e. "pie are squared."

Enthusiasts also note that the day happens to be Albert Einstein's birthday, in addition to other birthdays on this day. It's also curious to note that the renowned science and technology university Massachusetts Institute of Technology, known for its sometimes unconventional, quirky take on math, often mails out its acceptance letters to be delivered to prospective students on Pi Day.

The "ultimate" pi moment occurred on March 14, 1592, at 6:53 AM and 58 seconds. When written in American-style date format, this is 3/14/1592 6:53.58, which corresponds to the value of pi to twelve digits: 3.14159265358. However, considering this was well before any kind of standardized world time had been established, and the general public had no concept of π, the occurrence likely went unnoticed.

Source: Wikipedia



Have some pie on Pi Day,

Knight42092