A bungee cord is an elastic cord composed of one or more elastic strands forming a core, usually covered in a woven nylon or cotton sheath. Specialized bungees, such as some used in bungee jumping, may be made entirely of elastic strands.
Bungee cords were originally used in parachuting to assist in opening the old-style parachute container after the ripcord was pulled. Today, bungee cords are most often used to secure objects without tying knots and to absorb shock. Inexpensive bungee cords, with metal or plastic hooks on each end, are marketed as a general utility item.