In the concluding part of the article on Neutrinos and our Sun we discuss the detection of atmospheric neutrinos, their fluxes and zenith angle distributions. Here too one finds discrepancies with theoretical predictions. We discuss how the idea of neutrino oscillations helps resolve both the solar neutrino puzzle (discussed in Part 2) and the discrepancy observed in atmospheric neutrino fluxes. This is followed by a discussion of neutrino masses and the recent confirmation of the neutrino oscillations in the KamLAND experiment.