We briefly review the physics of neutrino masses and mixings as derived from neutrino oscillation data and the existing limits. The smallness of neutrino masses is explained in terms of Majorana neutrinos with mass inversely proportional to a large scale where lepton number is violated. This scale is well compatible with the Grand Unification scale. In this general context possible models for neutrino masses and mixings are concisely presented.
展开▼