Every year, March 14th brings a lot of cheer into the faces of students & scholars from around the world. What's the secret to this?

The constant Pi. Yes, you heard it right. It is the same one you use to calculate area of a circle in your Math class.

There are a lot of other constants out in the world in fields of Physics, Chemistry, Math and other sub-disciplines. But Pi stands out as the winner amongst them. We decided to answer your burning questions about Pi and its position in the world. Let's decode the mystery behind this magical albeit

*irrational*constant.

1. What is Pi?

Pi, deriving its name from the Greek letter 'π' (learn how to type Pi on your computer) - and has the value 3.14 approximately (there's a lot more where that came from).

2. No, like really, what is Pi?

We've all heard the boring definition of Pi in Mathematics - the ratio of a circle's circumference C to its diameter d.

Well, we're going to let you define what Pi is. Are you up for the challenge?

There you go - you are now in the league of mathematicians from ancient times! Pat yourself on the back for calculating Pi all on your own!

The value of Pi that you calculate this way will be a few decimal points off from the original value or even less than 3.0 at times. This kind of inaccuracy lead to the quest of finding the true digits that constituted the value of Pi.

3. How much of this Pi constant do we know today?

Mathematicians early in the day derived the value of Pi, but there was a lot of inaccuracy. With the times, mathematicians have constantly been trying to improve the accuracy by using different methods. It started off with accuracy upto 2 decimal places to 13.3 trillion (10^13) digits as of 2015!

4. So many digits! Where does Pi end?

Pi is an irrational number i.e. it cannot be expressed as a fraction, only as a decimal. Pi is also a non-terminating decimal. What does that mean?

This means that

5. Does anyone even care to remember more than 2 decimal places of this number?

Yes, memorizing and recalling the digits of Pi is a thing! The official world record for recalling the maximum number of digits of Pi is held by Rajveer Meena, an 21-year old Indian student from VIT University, Vellore in 2015. It took him 10 hours to recall 70,000 digits of Pi.

The unofficial record, however, is held by Akira Haraguchi, a Japanese engineer. He recalled around 100,000 digits in a span of 16 hours.

6. Whoa! People are crazy about Pi. Tell me something cool I can do!

You can look for your birthday or your lucky number in the digits of Pi. Want to look for the meaning of life '42' here? The possibilities are finitely infinite!

7. Nice! Why is March 14th Pi Day though?

March 14th, 2015 was Pi day accurate to 4 decimal digits i.e. 3/14/15. And March 14th, 2016 (today), is "Rounded Pi Day", i.e. 3/14/16 (rounding off 3.14159). 2015 & 2016 are the 2 honorable years that truly denote Pi Day in this century. The next possibility is only in 2115 & 2116!

__What you need__: A compass, a measuring tape (the flexible ribbon type), a pencil and a calculator.__Steps to find Pi__:**Step 1.**Draw a circle of any radius of your choosing using a compass. Mark the center with a pencil.**Step 2.**Measure the diameter d & circumference C of this circle with the measuring tape.**Step 3.**Calculate the value of C/d by hand or by using a calculator.There you go - you are now in the league of mathematicians from ancient times! Pat yourself on the back for calculating Pi all on your own!

The value of Pi that you calculate this way will be a few decimal points off from the original value or even less than 3.0 at times. This kind of inaccuracy lead to the quest of finding the true digits that constituted the value of Pi.

3. How much of this Pi constant do we know today?

Mathematicians early in the day derived the value of Pi, but there was a lot of inaccuracy. With the times, mathematicians have constantly been trying to improve the accuracy by using different methods. It started off with accuracy upto 2 decimal places to 13.3 trillion (10^13) digits as of 2015!

4. So many digits! Where does Pi end?

Pi is an irrational number i.e. it cannot be expressed as a fraction, only as a decimal. Pi is also a non-terminating decimal. What does that mean?

*If you divide 7 by 11, the answer is 0.6363636363.. and it keeps repeating these 2 numbers. This is a*__terminating (or repeating) decimal__.*Pi, on the other hand, 3.14159265359.. with no repeating pattern that ends it. This is a*__non-terminating decimal.__This means that

**nobody knows the last digit of Pi**in the living world. It is as infinite as the universe for all we know!5. Does anyone even care to remember more than 2 decimal places of this number?

Yes, memorizing and recalling the digits of Pi is a thing! The official world record for recalling the maximum number of digits of Pi is held by Rajveer Meena, an 21-year old Indian student from VIT University, Vellore in 2015. It took him 10 hours to recall 70,000 digits of Pi.

The unofficial record, however, is held by Akira Haraguchi, a Japanese engineer. He recalled around 100,000 digits in a span of 16 hours.

6. Whoa! People are crazy about Pi. Tell me something cool I can do!

You can look for your birthday or your lucky number in the digits of Pi. Want to look for the meaning of life '42' here? The possibilities are finitely infinite!

7. Nice! Why is March 14th Pi Day though?

March 14th, 2015 was Pi day accurate to 4 decimal digits i.e. 3/14/15. And March 14th, 2016 (today), is "Rounded Pi Day", i.e. 3/14/16 (rounding off 3.14159). 2015 & 2016 are the 2 honorable years that truly denote Pi Day in this century. The next possibility is only in 2115 & 2116!

8. March 14th. Is this day important otherwise?

Well, yes, today is important to physicists as well! Albert Einstein was born on Pi Day, 1879. It is also the birthday of Michael Caine (Alfred from the Batman movies) today.

9. I get the Pi craze, but why is Pi so much more important than the other constants we know?

Well, Pi appears in a lot of important formulas from time immemorial. It even features in the formula of Einstein's field equation of general relativity and Heisenberg's uncertainty principle among others. Without Pi, we would have been in another time altogether, living as cave people, foraging & hunting for food.

The formulas mentioned above require a very accurate value of Pi, since they deal with values so small & objects so atomic that rounding off a single digit can cause miscalculations!

Well, Pi appears in a lot of important formulas from time immemorial. It even features in the formula of Einstein's field equation of general relativity and Heisenberg's uncertainty principle among others. Without Pi, we would have been in another time altogether, living as cave people, foraging & hunting for food.

The formulas mentioned above require a very accurate value of Pi, since they deal with values so small & objects so atomic that rounding off a single digit can cause miscalculations!

10. Whoa. Pi seems so complex and scary.

It's not scary at all. In fact, it's the sweetest constant ever - the value of Pi is 3.14, which looks like PIE when mirrored. Well, no one can ever say no to pie!

So celebrate Pi Day today (technically, Rounded Pi Day, you know why), and tell your friends why they should too!

And as always, keep learning.

And as always, keep learning.

*Guess what? HashLearn Now offers a free one-month trial this exam season. All you need to do is download the app from Play Store. Sign up before 31st March to avail your free month!**We love feedback. Write to us, like us on Facebook and follow us on Twitter.*