This is PI!
Pi is used to calculate any measurements relating to a shape with no sides. Like a circle or an ellipsoid, also known as an oval. Pi has no end at all, is keeps going on and on with no pattern whatsoever in how it decides to place it's digits. Pi is the 16th letter of the Greek alphabet. Greek letters are often used to express mathematical terms that are constant, they don't change, like the sigma, shown on the left. Pi is very confusing. When you think about it, how did the mathematicians even come up with pi anyway? Why is it that when we look up digits of pi, we get can find 1 million of them? How do people calculate pi? It's very confusing to me too. I keep wondering, do people keep making up the digits? Did one mathematician invent it, and now its a universal truth? Or is it that there is a way to find pi, by using the area or circumference of a circle? I think about that whenever I think about pi because pi can be very confusing at times.