  The article gives a brief overview, aimed at nonspecialists, about the goals
and selected recent results of the detection of very-high energy gamma-rays
(energies above 100 GeV) with ground based detectors. The stress is on the
physics questions, especially the origin of Galactic Cosmic Rays and the
emission of TeV gamma-radiation from active galaxies. Moreover some
particle-physics questions which are addressed in this area are discussed.
