Virtual Compton Scattering at Low Energy and the Generalized Polarizabilities of the Nucleon o

Virtual Compton Scattering on the nucleon: $gamma^* N to gamma N$ is a new and rapidly developing field at low and high energies. This lecture is about the low energy part, i.e. for energies in the $(gamma p)$ center-of-mass mainly up to the $Delta(1232)$ resonance region. I review the concept of Generalized Polarizabilities of the Nucleon, and the experiments dedicated to their measurement.