Quantum electrodynamics in superconducting circuits 2.1 Some basics about superconductivity: zero resistance, Meissner-Ochsenfeld effect, critical magnetic field, Cooper pairs, the BCS gap 2.2 The Cooper pair box: tunneling between two islands, the charging energy, the tunneling term, external control via a gate charge [erratum: near the end of the lecture, the arrow for the dipole moment of the Cooper pair box was drawn in the wrong direction. It should point from the negative to the positive charge, as always.]