Celebrate Pi Day on March 14, 2013. If you are a number geek, it’s a great day to tell some Pi Day jokes, write your own “pi-ku”, share your love of numbers on the Pi Day Facebook page or explain what Pi is to your less informed friends.

**What is Pi? **Sorry, you can’t eat it. Pi is the symbol for the ratio of the circumference of a circle to its diameter. Pi = 3.1415926535….

Every year on March 14, Pi Day is celebrated by math enthusiast around the globe. The symbol for Pi was first used in 1706 by William Jones. It became popular after it was adopted by the Swiss mathematician Leonhard Euler in 1737.

In 2009, the US House of Representatives gave their support what is now designated as the official day to celebrate Pi.

**Why was March 14 picked to become Pi Day? **Celebrated on the fourteenth day of the third month, the first three digits of Pi are 3.14, so it makes perfect sense. Pi is a transcendental number, with digits after the decimal point that go on forever. Fortunately, the day won’t last forever if you aren’t a number lover.

**Pi Day jokes for your math loving friends:**

- What do you get when you take green cheese and divide its circumference by its diameter? Moon Pi.
- What do you get when you cut a jack o’lantern by its diameter? Pumpkin pi.
- What was Sir Isaac Newton’s favorite dessert? Apple pi.
- What do you get if you divide the circumference of a bowl of ice cream by its diameter? Pi a la mode.
- What do you get when you take the the sun and divide the circumference by the diameter? Pi in the sky.

**Write a Pi-Ku:**

Learn how to write one here.

**Get connected:**

- Join your Pi Day friends on the Pi Day Facebook fan page.
- Find more information on Pi Day on PiDay.org.