3/14 is considered to be Pi Day by many geeks, as π is ap­prox­i­mate­ly 3.14. I wish I could say that I had celebrated by eating pie, but I didn’t.

π is surely the most important irrational number, which has been known since antiquity.

π shows up in so many different formulas. My own favorite is Euler’s Identity, e^iπ + 1 = 0. (This marks the first use of the re­Struc­tured­Text math role in my blog.)

I am also find of the ap­prox­i­mate fraction 355 ⁄ 113.

The Wikipedia article on π has much more on π.

Update: Wonkblog: 10 stunning images show the beauty hidden in pi