## Pi Day

Today is Pi Day! No, not that kind of pie. Pi is the circumference of a circle (or the distance around a circle), divided by its diameter (the distance across). Essentially, the circumference of any circle is approximately 3.14 times its diameter. That's not exactly exciting information for most people, but there are some interesting facts about Pi!

- March 14th (or 3/14) is celebrated as Pi day, because 3.14 are the first digits of Pi.
- Most people think of Pi as the number 3.14, but since it's an irrational number, it actually has an infinite number of digits!
- The first known calculation of Pi, was done by Archimedes of Syracuse (287-212 BC), one of the most brilliant mathematicians of the ancient world.
- The Greek letter π is the first letter of the word periphery and perimeter. Pi itself, is the ratio of a circle’s “periphery” to its diameter.
- The calculation of Pi is often used as a stress test for a computer. Similar to a digital cardiogram, it indicates the level of activity within the computer's processor.
- Pi Day is also Albert Einstein's birthday!
- Pi has 6.4 billion known digits. It would take a person around 133 years to recite all of them without stopping.
- People in ancient Egypt believed that the pyramids of Giza were built upon the principles of Pi. The vertical height of the pyramids have the same relationship with the perimeter of their base, like the relationship between a circle's radius and its circumference.
- The world record for reciting the most number of decimal places of Pi, was achieved by Rajveer Meena in 2015. He was able to recite 70,000 decimal places, and wore a blindfold throughout the duration of his recall (which took 10 hours)!
- There is an entire language made from the number Pi, called "Pi-lish". The numbers of letters in each word match the corresponding digits of Pi.

Fascinating! The other kind of 'pie' still remains our favorite, though. What's your favorite kind of pie? We'd love to see pictures or recipes of you most delicious creations!