Results of the ARGO-YBJ experiment in detection of gamma rays

The ARGO-YBJ air shower detector has been in stable data taking for five years at the YangBaJing Cosmic Ray Observatory (Tibet, P.R. China, 4300 m a.s.l.) with a duty cycle > 86% and an energy threshold of a few hundreds of GeV. Besides working in shower mode, the detector used the scaler mode technique, which can reach the minimum threshold of 1 GeV. In this paper a selection of results in gamma ray astronomy will be presented, including those from the study of the diffuse emission from the Galactic plane.