In this master seminar we discuss elements of modern information theory and how they reflect in quantum mechanics as well as quantum field theory. After a general introduction to classical and quantum information we will discuss entanglement and how it can be detected. We will then dive deeper into convenient formalisms for quantum mechanics and quantum field theory, before we discuss an information theoretic formulation of Heisenbergs uncertainty relation and interesting twists to it that arise as a consequence of entanglement. The role of quantum information for thermalization in a quantum world as well as for Hawking radiation in the vicinity of black holes will also be discussed.