World is celebrating today Pi day and also this day coincides with great Albert Einstein Birthday. Pi day is celebrated because it resembles Pi value 3.14.
As from Wikipedia – Pi Day and Pi Approximation Day are two holidays held to celebrate the mathematical constant π (pi) (in the mm/dd date notation: 3/14); since 3, 1 and 4 are the first three decimal digits of π.
Albert Einstein Birthday is also celebrated today on March 14. This great Nobel Prize winner scientist born on March 14 1879 and is famous for his theory of Relativity e=mc^2.
Similar to Pi day, another Pi approximation day is celebrated on July 22. Its because of the Ancient mathematician Archimedes’ first rough approximation of π as being 22/7. However, this may be considered misleading, as all cited dates are “approximation days” (since π is an irrational number) and 22/7 is actually a closer approximation of π than 3.14 is. Typically, March 14 is more popular for countries using the month/day format and the 22nd of July is more popular for countries using the day/month format.