The discovery of neutrino oscillation verified that neutrinos have tiny but non-zero masses. However, in the Standard Model the neutrinos cannot have masses and hence the neutrino mass constitutes a solid proof of the existence of physics beyond the Standard Model. Many mechanisms for generating tiny neutrino masses have been proposed so far. In this talk, I will introduce some of those mechanisms and discuss the possible connections between neutrino mass models and other physics beyond the Standard Model. I will also briefly present my recent works on the models where the neutrino masses are radiatively generated.