Gamma-ray telescopes are specialized instruments designed to detect and study gamma rays, which are high-energy electromagnetic waves emitted by cosmic events. Unlike optical telescopes that observe visible light, gamma-ray telescopes focus on the most energetic phenomena in the universe, such as supernovae, black holes, and neutron stars. They help scientists understand the fundamental processes occurring in these extreme environments. These telescopes use various techniques, including pair production and Cherenkov radiation, to capture gamma rays. Notable examples include the Fermi Gamma-ray Space Telescope and the HESS Observatory. By analyzing gamma-ray data, researchers can gain insights into the origins of cosmic rays and the nature of dark matter.