When cosmic rays interact with nuclei in the Earth’s atmosphere they produce an abundant source of neutrinos over several decades in energy, from a few GeV up to several hundreds of TeV. These neutrinos can be used to study a wide range of interesting phenomena, such as hadronic production and interaction models, neutrino oscillations, and neutrino interaction cross sections at extremely high energies. Atmospheric neutrinos are also a valuable source in the search for new physics beyond the Standard Model of particle physics. The IceCube/DeepCore detector, located at the South Pole, is a cubic kilometer-sized Cherenkov detector that is sensitive to neutrinos from about 6 GeV up to several PeV in energy. I will present the latest results from this experiment with an emphasis on the measurements obtained using atmospheric neutrinos. I will also report on the status of the proposed IceCube-Upgrade, which aims to deploy new optical modules into the South Pole ice along with new calibration devices, and would serve to greatly improve both the precision of our neutrino measurements and the understanding of the IceCube/DeepCore detector.