Pi is a mathematical constant that is the ratio of a circle’s circumference to its diameter, and it is also one of the most revered mathematical constants in the known world. Pi Day was first officially celebrated on a large scale in 1988 at the San Francisco Exploratorium. Since then, Pi Day has been celebrated by millions of students and math-lovers. The holiday is celebrated on 14th March, since 3, 1, and 4 are the three most significant digits in the decimal form of pi. If you’d like to learn how to celebrate pi in due fashion, read on and it will be as easy as pi.