How was the number π first discovered? How did we first figure out it was 3.14…? - craftyguy
======
greenyoda
Pi is defined as the ratio of a circle's circumference to it's diameter.
Someone could have discovered that this ratio was a constant just by measuring
circles of different sizes and noticing that if you divide the circumference
by the diameter, you always got roughly the same number. By ancient times, the
value of pi was already known to within 1%:

[https://en.wikipedia.org/wiki/Pi#Antiquity](https://en.wikipedia.org/wiki/Pi#Antiquity)

------
byoung2
[https://en.wikipedia.org/wiki/Pi#History](https://en.wikipedia.org/wiki/Pi#History)
offers a few explanations from different eras

