Twitter (TWTR), Chipotle (CMG) pop on big earnings beats >>> READ MORE

# Pi Day: What Is Pi?

## Mathematicians celebrate March 14

It’s March 14 everyone! Or as the mathematicians out there call it, Pi Day.

Source: Wikipedia

Pi Day may seem like a joke holiday only celebrated by math teachers, but it’s actually a national holiday. Sure, the banks don’t close down and schools are still open –so kids can learn about Pi of course– but that didn’t stop America from naming it a national holiday in 2009, reports The Atlanta Journal Constitution.

What exactly is Pi? Here is how Live Science describes the mathematical term.

Pi (π), the 16th letter of the Greek alphabet, is used to represent the most widely known mathematical constant. By definition, pi is the ratio of the circumference of a circle to its diameter. In other words, pi equals the circumference divided by the diameter (π = c/d). Conversely, the circumference is equal to pi times the diameter (c = πd). No matter how large or small a circle is, pi will always work out to be the same number.