A telescope is an optical instrument designed to gather and amplify electromagnetic radiation, primarily visible light, from distant celestial sources. Its function involves using sophisticated arrangements of lenses or curved mirrors to collect photons over a large collecting area and subsequently focus them into a manageable beam. By concentrating the faint light from faraway objects, the instrument increases the apparent brightness and angular size of the targets, enabling observations that would otherwise be impossible to resolve. Modern advancements have moved beyond visible spectrum observation, incorporating different types of detectors to detect various forms of radiation, including radio waves, infrared, and X-rays, thus expanding the observable range of astrophysical phenomena.