Neighbourhood Of Any Point

Question

What does it mean to say that $x \to c$, can $x$ and $c$ be both variables, can $x$ and $c$ be both constants?

Answer 1

It depends on the context, but generally $x$ is a variable and $c$ is a fixed constant.

As $x \to c$ means as $x$ approaches $c$, probably from all directions in $2$ dimensions given the title.