The OPERA experiment was designed to study v mu -> v(tau) oscillations in appearance mode using the CERN to Gran Sasso high energy neutrino beam. From 2008 to 2012, 19505 CNGS neutrino interactions were recorded in the OPERA detector. At the present status of the analysis, 4 v(tau) candidate events have been observed, establishing the oscillation mechanism in the atmospheric sector with a significance of 4.2 sigma. The oscillation analysis will be presented in detail and the candidate events will be described. The final measurement of the atmospheric muon charge ratio in the TeV region will be also reported.