What is Pi Day?
By TOI Desk Report
March 14, 2025
Update on : March 14, 2025
Math enthusiasts from college students to rocket scientists celebrate Pi Day on March 14th (3/14) around the world.
Pi is a Greek letter “π”. It is the symbol used in mathematics to signify a constant, which is approximately 3.14159. It is considered the ratio of the circumference of a circle to its diameter.
To mark the day, math enthusiasts narrate the infinite digits of Pi, talk to their friends about math, and eat pie–sweet, savoury or even pizza.
The day is an annual opportunity for the math enthusiasts.
Pi is over 50 trillion digits beyond its decimal point. The number will continue infinitely without repetition or pattern as it is an irrational and transcendental number.
Pi’s infinite nature makes it a fun challenge to memorize while only a handful of digits are needed for typical calculations.
If you think simply, pi is a mathematical constant to express the ratio of a circle’s circumference to its diameter.
Its numerous formulas are used in physics, astronomy, engineering and other fields. The use of numbers began in ancient Egypt, Babylon and China thousands of years.
Physicist Larry Shaw started celebrations of Pi Day at the Exploratorium Science Museum in San Francisco in 1988, but the holiday could not achieve national recognition.
Congress in 2009 designated the day every March 14 in the hopes of spurring more interest in math and science. The day is also birthday of Albert Einstein.
Why is it called pi?
As Welsh mathematician William Jones began using the Greek symbol for the number, it wasn’t given its name until 1706.
How Do People Celebrate Pi Day?
People celebrate Pi Day in different ways, such as, eating Pie, Math Challenges, Pi Recitation Contests, and Science and Math Events.