A Moduli Stack is a mathematical structure used in algebraic geometry to study families of geometric objects, such as curves or surfaces, that can vary continuously. It generalizes the concept of a moduli space, which classifies objects up to certain equivalences, by allowing for more complex situations where objects can have additional symmetries or structures. In a moduli stack, points represent isomorphism classes of objects, while the stack structure captures the automorphisms of these objects. This makes it particularly useful for studying objects like vector bundles or algebraic curves that may have non-trivial automorphisms, providing a richer framework for understanding their properties and relationships.