A "kite line" is the string or cord used to control a kite while it is flying. This line connects the kite to the flyer, allowing them to maneuver the kite in the air. Kite lines can vary in length and material, with some made from nylon or polyester for durability. The strength and thickness of a kite line are important, as they must withstand the forces exerted by the wind and the kite. Different types of kites may require specific line characteristics to ensure optimal performance and safety during flight.