A chocolate pie is pictured at Just Pies on Thursday April 4, 2019. Just Pies is located at 2970 Old Henderson Hwy. in Tyler. (Sarah A. Miller/Tyler Morning Telegraph)

It is never-ending. It is infinite. It is… pi.

No, not that kind of pie — the delicious baked dish of whatever filling your heart desires.

Pi, as in the mathematical constant, is celebrated each year as Pi Day on March 14.

This date came to be called Pi Day because when it is written in the month/day format, as 3/14 or 3.14, it’s the same as the first three digits of pi.

As a number with a decimal with no repeating pattern, pi is the definition of an irrational number.

According to piday.org, typing π into a calculator and pressing ENTER will yield the result 3.141592654, not because this value is exact, but because a calculator’s display is often limited to 10 digits.

Credit for Pi Day goes to Larry Shaw, the “Prince of Pi”, who invented the holiday in 1988 while at an off-site staff retreat at San Francisco’s Exploratorium.

To build on the idea, Shaw’s coworkers had a mini-celebration with just the staff, which included eating pies.

The next year, the holiday was held for all at the museum and every year since, even when the museum was closed during its move.

The celebration includes a parade at 1:59 p.m. with visitors holding a sign with a digit of pi, a pi shrine, eating of pies (fruit and pizza), singing happy birthday to Albert Einstein, and more.

Pi Day was recognized as a national holiday in 2009 and is internationally celebrated each year.

In 2015, it was proclaimed (by Shaw) to be a special year, as it was written 3/14/15, and he called it the “Pi Day of the Century.”

He felt the best thing about Pi Day was making math more accessible, fun for all.

Places like Mathnasium in Tyler definitely made math more engaging and fun with activities, games and prizes to commemorate Pi Day.

The local tutoring center celebrated Pi Day by expanding on circles, including snacks (like crackers and cookies).

“We have had a marvelous day here, been a lot of fun,” Mathnasium Director Annette McKee said. “The kids really enjoyed learning about the circles… and they had fun with the activities!”

Pi Day served as the perfect excuse to go to a local bakery and indulge in pies of all sorts, and customers could be seen doing just that Tuesday afternoon.

Four-year-old Tylerite Maximus Pugmire was one of those happy customers, who enjoyed a slice of chocolate pie at Just Pies. The Tyler bakery at 2970 Old Henderson Highway served slices of pie for $3.14 all day to celebrate the occasion.