Gliders are aircraft designed for sustained flight without an engine. They rely on rising air currents, known as thermals, to stay aloft. Pilots control gliders using a system of wings and rudders, allowing them to maneuver through the sky. Gliders are often used in recreational flying and competitive sports, where pilots aim to cover long distances or perform aerobatic maneuvers. These aircraft can be towed into the air by a powered plane or launched from a hilltop. Once airborne, gliders can glide for hours, making them popular among enthusiasts. The design of a glider emphasizes lightweight materials and aerodynamic shapes to maximize efficiency and performance.