Status and perspectives of GLAST gamma ray experiment

GLAST, the Gamma-ray Large Area Telescope, is a satellite-based experiment able to measure the cosmic gamma-ray flux in the energy range between 20 MeV and 300 GeV or above. The sensitivity is more than 30 times respect to EGRET and the good spatial and time resolution over a large field of view let us to cover a large variety of high energy phenomena. In particular GLAST will be able to study both diffuse emission and point-like gamma ray sources, including active galactic nuclei, gamma ray bursts, pulsars and supernova remnants. In addition, the potentialities of GLAST to explore rare or exotic phenomena like supersymmetric dark matter annihilations will be shown. The present knowledge of the science opportunities that the GLAST experiment can explore will be completed with the detector description and the current status of the experiment.