I realize that this question might seem ambiguous, is there a topological notion for what a Hole is? I think it has something to do with the fundamental groups of the topological space but I don't really know, could someone please tell me the basics and what is a basic tool for detecting when a topological space has "holes"?
Background: I am currently taking topology 1 and I am halfway through my second semester of abstract algebra.
Thank you kindly, regards.