I will review the basics about "Cosmic Strings" -- topological defects in the vacuum of some particle physics models. I will explain how the geometry around a string is either a conical deficit, or a highly nontrivial self-compactified manifold, depending on the nature of the broken symmetry of the vacuum. Time permitting, I will discuss how strings and black holes interact, and how the simple "cut a deficit out" prescription is not quite the whole story.