What are different diameters used for?
In general, the thicker the rope, the more of a beating it can withstand. Thats not always the case, of course, but its a good rule of thumb when setting out to buy a rope. When people opt for thin cords, they do so most often because theyre lighter and produce less friction (rope drag) over long climbs. When people opt for thicker cords, they do so most often because they intend to toprope a lot or fall a lot when working a climb. THIS isnt a complete reference, but its a good start.
