The term „Quantum Gravity“ refers to a multitude of approaches, whose goal it is to unify general relativity with the principles of quantum field theory. This involved the replacement of classical field variables by operators on a Hilbert space. Only statistical propositions about physical observables can then be made. The theory of loop quantum gravity is a particular, especially promising candidate for a theory of quantum gravity, since its mathematical construction is well-developed, when compared to other approaches. Loop quantum gravity is based on a gauge theory formulation of general relativity. This allows the application of well-established quantization methods from lattice gauge theory.