Today is Pi Day! March 14 or 3/14. Six years ago Numberphile published a couple of good videos about Pi. I shared them then and I think it’s time to share them again. Pi with real pies is a three minutes and fourteen seconds video that explains Pi and how it can be calculated.

After showing the video above, you might want to follow up with this video, How Pi Was Nearly Changed to 3.2.

And here is a more recent video about Pi produced by Numberphile. It’s titled A Mile of Pi. As you might guess, it’s about a mile of digits.