Classical Description of the Interaction of Light with Matter.- The Linear Dielectric Susceptibility General.- The Classical Treatment of Free and Bound Charge Carriers.- Derivations from the Oscillator Model.- The Kramers-Kronig Relations.- Interface Reflection and Interference Phenomena in Thin Film Systems.- Planar Interfaces.- Thick Slabs and Thin Films.- Extended Details: Gradient Index Films and Multilayers.- 9 Special Geometries.- Semiclassical Description of the Interaction of Light with Matter.- Einstein Coefficients.- Semiclassical Treatment of the Dielectric Function.- Solid State Optics.- Basics of Nonlinear Optics.- Some Basic Effects of Nonlinear Optics.- Summary.