# Happy Tau Day

6/28 is τ Day.
Tau = τ = one turn around the circle = $\frac{C}{r}$ = 2π = 6.28318…
How do mathematicians celebrate τ Day?
Protest! Share anti-π propaganda.
And eat two pies…

## The Bloggers Weigh In

If you’re convinced and you’re wondering how to bring more widespread acceptance of tau, then all you need to do is start using it. At the start of anything where you’d normally use pi, simply write “For convenience, τ= 2π”, and then get on with your dramatically simpler and more friendly equations.