Theoretical insights into neutrino masses

The observed neutrino oscillations imply that neutrinos have small but nonzero masses. This necessarily requires beyond-the-Standard Model (BSM) physics. But the nature of neutrino mass (Dirac, Majorana, or something else) remains unknown. In this talk, we will review the current status of neutrino mass theory and the future experimental prospects of testing some well-motivated neutrino mass models.