What is removable discontinuity for a complex function?

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Can someone tell me the removable discontinuity and poles of a function in complex analysis?

I read the definition in the book but I cannot feel it. Is there a nice definition?

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The situation is just like the reals. A removable discontinuity is something like $\frac {z^2-4}{z+2}$ at $z=-2$. The function is not defined there, but there is a limit. If you just define the function to be $-4$ at $z=-2$ you have the function $z-2$, which is nicely continuous. A pole is something like $\frac 1{z^n}$ at $z=0$ for some natural $n$. The modulus of the function heads off to infinity as you approach the point.