Neutrino masses and oscillations: an overview

After an historical introduction showing how our understanding of neutrino properties has improved over time, we focus on the phenomenon of flavor oscillations. The formalism is detailed, first for two neutrino families, then for three; matter effects are explained. We finally give an overview of the present experimental status on oscillations, and indicate the future prospects. To cite this article: J. Bouchez, C. R. Physique 6 (2005).