  These lectures give an elementary introduction to the subject of four
dimensional black holes (BHs) in supergravity and the Attractor Mechanism in
the extremal case. Some thermodynamical properties are discussed and some
relevant formulae for the critical points of the BH effective potential are
given. The case of Maxwell-Einstein-axion-dilaton (super)gravity is discussed
in detail. Analogies among BH entropy and multipartite entanglement of qubits
in quantum information theory, as well moduli spaces of extremal BH attractors,
are also discussed.
