A Cassegrain telescope is a type of reflecting telescope that uses a combination of mirrors to gather and focus light. It features a large primary mirror that collects light and reflects it to a smaller secondary mirror. This secondary mirror then directs the light back through a hole in the primary mirror, allowing for a compact design. This design makes the Cassegrain telescope popular for both amateur and professional astronomers. Its ability to produce high-quality images while maintaining a shorter physical length compared to other telescopes makes it ideal for various astronomical observations and research.