A climbing rope is the strong nylon cord used by climbers for protection and safety while climbing. Ropes, the most basic piece of safety gear used by climbers, simply attach climbers to each other and the cliff as well as keep a climber from hitting the ground after a fall. Ropes are a climber’s best friend and his literal lifeline.
Climbing ropes have an inner core of woven fibers and an outer sheath of woven fibers. They are very elastic and dynamic, allowing for the rope to stretch and absorb much of the energy of a fall. Climbing ropes are made from 7.5mm to 11mm in diameter, with the thicker ropes the strongest and best for climbing, but also the heaviest. Thin light ropes are mostly used for alpine climbing in the high mountains were weight is paramount. Ropes under 9mm in diameter are also usually used in pairs. Climbing ropes come in two lengths: 165 feet (50 meters) and 200 feet (60 meters). The 200-foot climbing rope is increasingly become the standard length for American climbing, as it is in Europe. You should only buy and climb on ropes that are specifically designed for climbing activities and are approved and certified by the UIAA (International Union of Alpine Associations)—in other words, don’t go into your local Home Depot to buy a climbing rope!
Besides dynamic ropes, the kind used for climbing, there are static ropes which are stout cords that do not stretch when loaded. These are not used for climbing since they do not absorb the shock of a climber’s fall but instead transfer it to the climber and his gear. Static ropes are usually used for top-roping, rappelling, fixed ropes, and caving.