Happy Pi Day! Pi, of course, is the Greek letter Л. Do you remember learning that the circumference of a circle is Л time the radius squared? Л is an infinite number beginning with the digits 3.14. Today is 3/14, so we celebrate Pi Day!

Today is only Pi day to three digits – 3/14. But, two years ago, for a brief second, Pi was accurate to 10 digits – 3/14/15 at 9:26:53.

Larry Shaw created Pi Day in 1988 and it was approved by the US House of Representatives in 2009.

Today is also the birthday of Albert Einstein so Princeton, where he spent much of his life, sponsors a Pi Day celebration including Einstein look-alike contests and a pie eating contest. There’s also a Molecular Mixology Class at Einstein’s first Princeton home on Bayard Lane. The day ends with a Nerd Herd Smart Phone Pub Crawl starting at Yankee Doodle Tap Room at 5 pm.

It’s likely that we’ll celebrate Pi day with our favorite pi – a pizza pie for dinner!