# Tau

Tau, what is it?!

This is a mathematical constant you might see sometimes in frameworks, especially in P5.

This one's easy, it's just PI * 2! It's handy when you're trying to make circles, because most drawing tools work with a radius.

```
Math.PI * 2 == TAU;
// returns true, if your framework has the constant TAU
// Or create it yourself!
const TAU = Math.PI * 2;
```

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