Pi Day is celebrated on March 14th (3/14) around the world. Pi (Greek letter “π”) is the symbol used in mathematics to represent a constant — the ratio of the circumference of a circle to its diameter — which is approximately 3.14159. Pi Day is an annual opportunity for math enthusiasts to recite the infinite digits of Pi, talk to their friends about math, and eat pie.1

. . . and it was DELICIOUS!
References
1 “Pi Day | Celebrate Mathematics on March 14th”. 2022. piday. https://www.piday.org/.
Additional Reading
“22 Fascinating Facts About Pi(Π) That Will Make You Amazed”. 2023. Medium. https://ali.medium.com/22-fascinating-facts-about-pi-%CF%80-that-will-make-you-amazed-894d661df206.
Pi, the ratio of the circumference of a circle to its diameter — 3.1415926535 — is just the beginning. It keeps going forever without ever repeating, which means that contained within this string of decimals is every other number; your birth date, the combination to your locker, your social security number, etc. It’s all in there somewhere. And if you convert these decimals into letters, you would have every word that ever existed in every possible combination; the first syllable you spoke as a baby, the name of your latest crush, your entire life story from beginning to end, and everything we ever say or do. All of the world’s infinite possibilities rest within this one simple circle. Now, what will you do with that information; what it’s good for? Well, that would be up to you!
Dolasia, Kavi. 2022. “How Pi Day Became America’s Biggest Math Holiday”. DOGOnews. https://www.dogonews.com/2022/3/8/how-pi-day-became-americas-biggest-math-holiday.
Feldman, Barbara. 2021. “Pi Day”. Resources » Surfnetkids. https://www.surfnetkids.com/resources/pi-day/.
“Pi Day – Fun Holiday”. 2022. timeanddate.com. https://www.timeanddate.com/holidays/fun/pi-day.
“Student Project: 18 Ways NASA Uses Pi | NASA/JPL Edu”. 2022. NASA/JPL Edu. https://www.jpl.nasa.gov/edu/learn/list/oh-the-places-we-go-18-ways-nasa-uses-pi/.
Whether it’s sending spacecraft to other planets, driving rovers on Mars, finding out what planets are made of or how deep alien oceans are, pi takes us far at NASA. Here are just some of the ways pi helps us explore space.
“Student Slideshow: The NASA Pi Day Challenge – NEW For 2022 | NASA/JPL Edu”. 2022. NASA/JPL Edu. https://www.jpl.nasa.gov/edu/nasapidaychallenge/.
Can you use π (pi) to solve these stellar math problems faced by NASA scientists and engineers? Explore the newest puzzlers in the 2022 NASA Pi Day Challenge below. Answers arrive here on March 15!
“The Weirdest Pi Day Facts You And Your Kid Will Enjoy”. 2022. lifehacker. https://lifehacker.com/the-weirdest-pi-day-facts-you-and-your-kid-will-enjoy-1848637107.