Answer
$\lim\limits_{x \to \ 0}f(x)=-1$
Work Step by Step
In order to obtain the limit of $\lim\limits_{x \to \ 0}f(x)$ we have to trace the graph.
We only have to consider the limit, not the value of $f(0)$.
As we trace the graph, we can observe, that as we approach 0 from both sides, the function converges to $-1$.
Therefore we can conclude, that the limit exists, it converges to $-1$ $\lim\limits_{x \to \ 0}f(x)=-1$.
