Pi

Pi (pronounced like pie) is a very special number in math, and because it's so special we give it it's own symbol π (which is the Greek letter pi).

Most calculators will have a π button, but a lot of the time when we need to use π we just use 3.14 instead. Pi was discovered thousands of years go without the interactive tools you used before.

Click on the "discovering pi" button below to explore how the mathematician Archimedes correctly estimated pi to be between 3.1408 and 3.1428 thousands of years ago.