Happy Pi Day!
It's not the kind you eat, but rather the symbol used in mathematics to represent a constant - the ratio of the circumference of a circle to its diameter.
While that may thrill the mathematically inclined, most of the population will be using today to enjoy the sweet treat, with many companies around the world jumping on board with special 'Pi Day' offerings.
Pi, the mathematical term, has been calculated to over one trillion digits beyond the decimal point, but to most of us, it's simply 3.14
courtesy Neil deGrasse Tyson (Twitter.com/@neiltyson)