Traditional versus sports climbing. Traditional climbing demands that one place one's own hardware on the surface being climbed. Sport climbing uses preexisting bolts. Traditional climbing is, by most accounts, the more demanding and aesthetically pleasing approach to climbing. At Rumney, however, traditional climbing is often impractical due to the comparatively soft rock composition.
On belay. One way or another, except in rare instances, climbers are suspended by ropes. A person at the bottom of the climb runs a rope -- which is securely anchored at the top of the climb -- through a belaying device attached to his or her harness. Using friction, the device retards the passage of the rope sufficiently to "catch" a climber if she or he falls.
Bouldering. A verb in climbing, bouldering can revolve around a "problem" or a specific challenge -- an interesting set of handholds or a mild traverse -- that trains the climber for later attempts at the mountain. Often, bouldering is performed without a rope. Instead, climbers bring bouldering mats and spot one another as each person climbs.
Lines. Lines are the specific paths up a rock face. The first person to perform the ascent, or the person who sets the bolts, is given the job of naming the climb, and the results can be colorful. Rumney lines, for example, include Flesh for LuLu, A Week with Pete, Who Done It, and Pretzel Logic.
The Yosemite Decimal System. The difficulty of a given climb is subjective, but climbers use a somewhat peculiar decimal system as a shorthand for describing a climb. A climb is a 5-point-something, a 5.4 being theoretically easier than a 5.6, for example. As a shading device, and only when a climb is at least a 5.10, climbs are given a letter at the end so that a climb can be a 5.10b.