(Chapter Heading): Zero-Point Energy in Early Quantum Theory. The Electromagnetic Vacuum. Some QED Vacuum Effects. Nonrelativistic Theory of Atoms in Vacuum. Interlude: Radiation Reaction. The Vacuum in Quantum Optics. Casimirand van der Waals Forces: Prelude. Casimir and van der Waals Forces: Elaborations. The Dirac Equation. Introduction to Quantum Field Theory. Self-Energies and Renormalization. Feynman Diagrams. Appendices: Oscillator Equation and Absorption Rate. Force onan Atom in a Thermal Field. Derivation of Equation (2.28). Electric Field of Radiation Reaction. Photodetection and Normal Ordering. Transverse and Longitudinal Delta Functions. Lorentz-Invariant Measure. Index.