March 14 - Pi Day

March 14 is celebrated by math fanatics everywhere as Pi Day. Pi, the Greek letter (), is the symbol for the ratio of the circumference of a circle to its diameter. Pi = 3.1415926535, and March 14 also happens to be the birthday of the genius, Albert Einstein. Naturally, it's no surprise therefore that Pi Day and Einstein's birthday are celebrated together.

July 22 - Pi Approximation Day

Pi Approximation Day is celebrated on July 22, because of the Ancient Greek mathematician Archimedes' first rough approximation of Pi (p) as being 22/7.

What Is Pi?

As outlined above, Pi = 3.1415926535. The Greek letter Pi (), is the symbol for the ratio of the circumference of a circle to its diameter. Pi's actual ratio comes from nature itself - it's the ratio between the circumference of a circle and its diameter, and it always existed, but who really discovered its existence? It's hard to pinpoint who exactly was the first to become conscious of the constant ratio between the circumference of a circle and its diameter, as human civilizations were seemingly aware of it from as early as 2550 BC. The earliest textual evidence of pi dates back to around 1900 BC, when both the Babylonians and the Egyptians had a rough idea of its value. The Babylonians estimated pi to be about 25/8, while the Egyptians estimated it to be around 256/81. The Ancient Greek mathematician Archimedes of Syracuse (287-212 BC) is however largely considered to be the first person to accurately calculate an estimation of the value of pi. He achieved this by finding the areas of two polygons.