TIL about Tau (τ), a mathematical constant that is the ratio of a circle's circumference to its radius, that in 2010 was proposed to be the replacement of π.

https://en.wikipedia.org/wiki/Tau_(mathematics)
#til #todayilearned
https://www.reddit.com/r/todayilearned/comments/1rtlmex/til_about_tau_τ_a_mathematical_constant_that_is/