Numerical zeros of a nonnegative function?

Question

Suppose we have a function $f:\mathbb{R}^{n}\rightarrow \mathbb{R}$ that satisfies $f\left(x\right)\geq 0$, for every $x\in\mathbb{R}^{n}$. What is the good numerical way of finding points $x_{0}\in\mathbb{R}^{n}$ that satisfies $f\left(x_{0}\right) = 0$? One way is to minimize that function, but what are the other ways?