**HapPi Day, Everyone!**

Yesterday (March, 14) people around the world celebrated Pi Day. Pi, known as Greek letter, “π”, is mathematics symbol that represents the ratio of circumference of a circle and its diameter (3.141592…). It is celebrated on March 14 every year. March 14 is chosen since it is the first three digits of this never ending number 3.14. Interestingly, it is Albert Einstein birthday as well.

The earliest celebration of Pi Day was organized by physicist Larry Shaw 30 years ago at the Exploratorium, a science museum in San Francisco. On March 12, the U.S House of Representatives recognized March 14 as the National Pi Day. People from students, teachers, mathematician and pie lovers alike celebrate this day with different creative ways till today.

**How People Celebrate Pi Day**

People all over the world, from schools to tech giants, came up with quite interesting ideas in celebrating. Students were eating pies and wearing pi-themed costumes to school. Microsoft offered a 31.4 percent discount on a selection of computers, which is apparently their tradition every year. Twitter users are celebrating by making the hashtag #PiDay the trending topic yesterday. Bloggers or YouTubers who are famous with their mathematics content also uploaded special videos to celebrate the occasion.

Even everyone out there who does not enjoy numbers in daily life and have only the slightest idea about what Pi is, joined the event by celebrating “pie” or “pi”-zza day, just to join the fun. In USA, famous pizza joints like Domino and Pizza Hut were giving away pizzas with their own respective deals. People were baking their own pi-themed pies and uploaded it on Twitter.

That how popular Pi day is.

**History of Pi**

The famous number in Mathematics which is denoted by the Greek alphabet, π, translated as *pi* and pronounced as ‘pie’ as in ‘apple pie’. Pi is the symbol that represents the ratio of circumference of a circle to its diameter that was approximately equal to three. So, by its definition, pi equal to the circumference divided by the diameter. In 287-212 B.C., Archimedes of Syracuse one of the greatest mathematicians has carried out the first calculation of pi. He used Pythagorean Theorem to find the areas of two regular polygons to approximate the area of a circle. As a resulted, he showed that pi is between 3 1/7 and 3 10/71.

In fact, Pi has been known for almost 4000 years, but it’s still a kind of approximation. In 1761, Johann Heinrich Lambert the Swiss Scientist found that pi is irrational number. It can not be represented as a ratio of two integer numbers. In the other words, pi known as a never ending number or an infinite decimal (3,141592…).

Actually, in this 21st century, mathematicians and computer scientists find a new approach as a combination of computer technology and computation to calculate a representation of pi to over ten trillion digits beyond its decimal poin.. But still, the exact value of pi has never been proven.

**Interesting Little Facts of Pi**

Want to find some interesting facts about Pi? Here they are.

- Pi is the 16th letter of Greek alphabet, while p is the 16th letter of English alphabet.
- The value of Pi has been calculated to more than 2 trillion digits
- Albert Einstein was born on March 14, the Pi Day.
- Rajveer Meena of Vellore from India is recorded as people who memorized for the most digit of Pi in 2015, reciting 70.000 decimal places of Pi.
- William Shanks worked on hand to find 707 digits of Pi and made mistake after the 527th place. So, all following digits were wrong.
- The first million decimal places of pi consist of 99,959 zeros, 99,758 1s, 100,026 2s, 100,229 3s, 100,230 4s, 100,359 5s, 99,548 6s, 99,800 7s, 99,985 8s, and 100,106 9s
- Al Khawarizmi, a mathematician from Baghdad, calculated the value of four digits of Pi, 3.1416.
- Isaac Newton calculated pi to at least 16 decimal places.

**What Makes Pi is so Unique? **

Apart from representing the ratio of circumference of a circle, surprisingly Pi has so many useful benefits in our life. Here is a list of how Pi is used in other fields.

- Pi is used in characterizing and searching for new planets outside our solar system.
- Pi helps Astrophysicists describe the shape of universe
- Pi is used by a lot of Physicists in Large Hadron Collider (the $10 billion machine at the European Organization for Nuclear Research (CERN) in Switzerland. This machine is using for as-yet-undiscovered particles such as the Higgs boson, which is refered to as “the God particle”
- Pi also used in Albert Einstein’s equation for how energy and mass lead to the curvature of space-time
- Pi is an important part of G (Newton’s constant for gravitation)
- Pi has an important role in the way how DNA is folds
- Pi is used in studying crickets – how accurately crickets walk towards sound.
- Pi exist in James Clerk Maxwell’s equations of electromagnetism in the 1860s which are fundamental to modern electronics and communications.
- Pi is used to calculate the surface area and volume of round three-dimensional objects in engineering
- Pi is also used by Chandrajit Bajaj at the University of Texas, Austin in her research; molecular recognition models for drug design and discovery.

This concludes that there are more than 3.14 reasons why we celebrate Pi day yesterday.

HapPi day everyone! and let’s have some Pi(e).