"It's all in the crust" at Just Pies. (Jennifer Scott/Tyler Morning Telegraph)

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

No, not that pie — the delicious baked dish of whatever filling your hearts desire. Pi, 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.

In Tyler, celebrations were held to commemorate the day, including the Tyler Public Library’s 4th Annual Pi Day Competition, where participants showcased made-from-scratch pies in three categories: cream/meringue, fruit/lattice, and savory.

Meanwhile, local businesses embraced the spirit of the day with themed specials: Just Pies, located at 2970 Old Henderson Highway, offered slices for just $3.14 each, while recently-opened Parry’s Pizzeria & Taphouse, at 3314 Troup Highway, served up 9-inch cheese pan pizzas for the same price — because pizza, after all, is just another kind of pie.

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. (a nod to the next few digits of pi) with visitors holding a sign with a digit of pi, a pi shrine, eating 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.