An X-ray telescope is a specialized instrument designed to observe celestial objects that emit X-rays, a form of high-energy radiation. Unlike regular optical telescopes that capture visible light, X-ray telescopes use mirrors and detectors to focus and measure X-rays from sources like black holes, neutron stars, and supernova remnants. These telescopes are often placed in space to avoid Earth's atmosphere, which absorbs X-rays. The data collected by X-ray telescopes helps astronomers understand the universe's most energetic phenomena. Notable examples include the Chandra X-ray Observatory and the XMM-Newton, both of which have provided valuable insights into the structure and behavior of cosmic objects.