Add to ORKGThe Pierre Auger Observatory has been designed to investigate the origin and the nature of Ultra High Energy Cosmic Rays using a hybrid detection technique. It is located on a plateau in the Province of Mendoza, Argentina, and consists of a surface array of about 3000 km2 overlooked by 24 air fluorescence telescopes grouped in 4 sites which together provide a powerful instrument for air shower reconstruction. The southern of the Auger Observatory has been completed in June 2008 and it is taking data smoothly since 2004. A review of selected results is presented with the emphasis given to the measurement of energy spectrum, chemical composition and search for photon and neutrinos as primary particles