Pi remains something of a mathematical phenomenon. While plenty of us may be aware of it through pop culture (and even a handful of math lessons going back years), it’s a staple that continues to fascinate number-crunchers the world over. But what exactly is pi, anyway? Before we get it confused with a tasty crust or two, here are some fun facts about pi worth remembering.

## 1. What exactly is pi, anyway?

Pi is a mathematical formula that’s used to calculate the circumference of a circle in relation to its diameter, the intersection that cuts across the middle. Pi is typically calculated as 3.14, but its full number is much longer!

## 2. Who invented the symbol for Pi?

The famous symbol for pi (π) was created by mathematician William Jones. He created the symbol back in 1706. However, it only started being commonly used thanks to Leonhard Euler.

## 3. How old is pi as a concept?

Although we only know of Pi as we see it today, having been used from the 18th century, there is proof to suggest that we have been using it for far longer! In fact, some believe that this proof dates back to about 4,000 years ago!

## 4. 3.14…

Many of us know the first few digits of pi; however, we would have to keep going to finish the number! Like many non-rounded numbers, it’s said to have an infinite number of decimal places.

## 5. Round and round we go…

In school, you will no doubt have learned that to calculate the circumference of a circle, you have to do the ‘pi times radius squared’ equation. However, giving a perfect answer with this equation is near impossible! Since Pi is supposedly endless, it is impossible to calculate it precisely – you could effectively never know what the exact circumference of a circle is!

## 6. Pilish?

Believe it or not, pi is about more than just numbers. In fact, it has its own language! If you fancy indulging in a bit of Pilish, then simply read Mike Keith’s book, Not A Wake, which was written entirely in vocabulary based around the mathematical phenomenon.

## 7. Pi-ramids!

Pi was most likely used in the building of the ancient pyramids of Egypt! It is believed that builders placed the pyramids where they are exactly to have a view of the perfect circumference. Now that’s some serious dedication to detail!

## 8. Calculating pi…

Thanks to modern computers, we have gotten farther in calculating Pi than ever before! In fact, the current record for calculating Pi is 62.8 trillion decimal places!

## 9. Memorizing pi isn’t easy!

As you can imagine, memorizing the entirety of pi is an impossible feat! However, the world-record holder for memorizing the number is Rajveer Meena, who recited 70,000 digits in just over nine hours! Does anyone else feel tired just reading about it?

## 10. Pi day!

There is indeed a Pi day! And, as you might have guessed, it is held every year on the fourteenth of March. That is because (depending on where you live) the date should show up as 3.14.

## 11. Your phone number exists as part of pi.

Want to know how big pi is? Let’s put it this way – there is a theory that every phone number in the world exists somewhere in pi’s endless run of numbers!

## FAQs about Pi

## Why is it called pi?

The term ‘pi’ came from Welsh mathematician William Jones, who named it as such due to the fact that the first letter in perimetros (Greek for perimeter) is pi.

## Who first used pi?

It is believed that the very first calculation of pi was by Archimedes of Syracuse. He lived from 287 BC to 212 BC.

## Why is pi so important?

It is said that pi is so important as it allows us to better understand the universe! It is commonly used in physics, and we wouldn’t be where we are today without it!

Do you know any fun facts about the pi? Share them in the comments below!