In the first part of the story of π, we discussed why the ratio of the circumference of a circle to its diameter is a constant. We talked about early attempts to bound the numeric value of π that began about four thousand years ago. We discussed Archimedes’ lower and upper bounds for π. We also talked about that why there are people still working to improve best current bounds. This four millennia long tale has a lot more to teach us!

In the second part, we will discuss some interesting intellectual puzzles related to π. For example, is it possible to express π as a fraction (i.e., ratio of two integers)? Is it possible to “square the circle (that is, can we construct a square whose area is equal to that of a given circle)? These, and other such questions, have occupied the collective minds of mathematicians for thousands of years.

The story of π is not only a tale of beautiful mathematical results but it is also a tale of perseverance, dedication, passion, success, failure, embarrassing wrong claims and human genius. We try to capture some of these too!