  While neutrino physics enters precision era, several important unknowns
remain. Atmospheric neutrinos allow to simultaneously test key oscillation
parameters, with Super-Kamiokande experiment playing a central role. We discuss
results from atmospheric neutrino oscillation analysis of the full dataset from
Super-Kamiokande I-IV phases. Further, we discuss tests of non-standard
neutrino interactions with atmospheric neutrinos in Super-Kamiokande.
