Who Invented Pi?

As many know, 3/14 is Pi day, and many are celebrating!

But who actually invented Pi?

The earliest written approximations of Pi were found in Egypt and in Babylon around 1900 B.C. The Babylonians treated Pi as 25/8 or 3.1250. The Egyptians treated Pi as 16/9 or 3.1605. 

The Ancient Greeks were the first to use an algorithm to figure out Pi. They used the Polygon approximation method created and applied by Archimedes. Around 250 B.C, Archimedes calculated that 223/71 < Pi < 22/7. He calculated Pi to two decimal points (3.1408 < Pi < 3.1429) and the 22/7 approximation that was used by mathematicians for centuries afterwards.

China also deserves mention for perfecting the method and creating more accurate estimations.

While many credit the famous mathematician Leonard Euler for introducing the symbol of Pi, the symbol was actually first used in 1706 by the mathematics teacher William Jones. π had been used in other works, but this was the first time it was used to represent the constant that we know today. He also believed that Pi was infinite and therefore could not be represented as a ratio. This was later proven by Johann Lambert.

There you have it, a brief history on who helped to create Pi. 

Sources:
http://www.historytoday.com/patricia-rothman/william-jones-and-his-circle-man-who-invented-pi
http://delphiforfun.org/programs/Math_Topics/Archimedes_PI.htm