## About PI

Pi, Greek letter (pi), is the symbol for the ratio of the circumference of a circle to its diameter. It is approximately 22/7 and is usually calculated to 3 digits, 3.14. With the use of computers, Pi has been calculated to over 1 trillion digits past the decimal. Pi is an irrational number meaning it will continue infinitely without repeating. The symbol for pi, pi, was first used in 1737 by William Jones, but was popular after it was adopted by the Swiss mathematician Leonhard Euler in 1737.