Lead Rock Climbing is a type of rock climbing, where the climbing technique known as "lead climbing" is used to ascend a route. This technique involves a lead climber attaching themselves to a rope and ascending a route, and preparing it for a climber behind them.

Sport lead rock climbing is a type of rock climbing where a lead climbers attach themselves to a length of dynamic climbing rope and ascend a route while at the same time attaching protection to the face of the rock; as climbers attach protection to the rock face, they then clip themselves in. Lead climbing is deemed to be a less restrictive form of climbing because it does not require a top rope, and the climber does not have any anchor points above them. Protective devices are only meant to catch the climber in case of a fall. When lead climbing, the lead climber or leader wears a harness tied to one end of a rope. The leader's partner provides the belay, paying out rope as needed, but ready to hold the rope tightly, usually with the aid of a belay device, to catch the leader in the event of a fall. The lead climber ascends the route, periodically placing protection for safety in the event of a fall.

The goal of lead climbing is to climb a rock face without a top rope to assist the climber.

Anchors
Dynamic Rope
Protective Devices

Lead climbing is an advanced rock climbing technique and should only be attempted by experienced climbers. The lead climber ascends the route, periodically placing protection for safety in the event of a fall. Distances between pieces of protection can range from three to forty feet or more, although most often the distance is between six and twelve feet. At any point, the leader can fall at least twice as far as the distance to the most recently placed protection. If a leader is ten feet above the last piece of protection, a fall will be a minimum of twenty feet.

Lead climbing is not a technique for novice climbers, and thus, those attempting a lead climb already have a great deal of experience rock climbing.

http://en.wikipedia.org/wiki/Lead_climbing