# Today is Pi Day!

Today is 25th Pi Day. March 14 (3.14) is Pi Day, a celebration of the ratio of a circle’s circumference to its diameter — one of the most beautiful and confounding numbers in mathematics. It’s technically written as 3.14159, or 3.14 for short.

Of course this only works in the American date format, but let’s all look past that to celebrate this crazy mathematical constant together. Bonus: it’s also Einstein’s birthday!

Even if you hate math, you’ll love Pi Day. Why? Because there’s pie.

Why does “pi” deserve its own day?

It’s a special number. It shows up everywhere. In chemistry, physics, math, whether you’re talking circles or cycles or anything to do with a curve, you’re going to find pi in there somewhere. Pi is irrational, which means that you can’t calculate pi by dividing an integer by any other integer. Pi never ends and it never repeats. People have to wrap their brain around that. Twenty-two over seven gives you a pretty good approximation of pi, but it’s not pi.

How far have we calculated pi now?

The current record for this noble endeavor is 10,000,000,000,050 decimal places, held by Alexander Yee and Shigeru Kondo. It took them 371 days to make the calculation with a dual-core Xeon PC running 96GB of RAM and 58TB in total storage.

It’s hard to imagine Pi Day didn’t exist until 1988

The first party in honor of the amazing mathematical entity known as “pi” began in 1988 when Larry Shaw, a physicist at the Exploratorium, the San Francisco science museum, looked at the calendar and said, “March 14—it’s the number pi. It’s Pi Day. Let’s celebrate!” Now Pi Day is marking its 25th anniversary.

[Note: This story must be true as I read this in Nat Geo]

We also celebrated the 25th Pi Day in Baghdad with Pizza in our dinner. Happy Pi Day!