The rock that climbers climb on is generally varied. In Britain the following types are common:
For example, Peak District gritstone has high friction and is generally strong and compact and vegetation free, but it is known for producing routes with very sparse protection.
Which rock is best to climb on is a discussion likely to cause great debate amongst some climbers.
Climbers grade the routes they climb. The grading system used varies from country to country (and region) and according to what style the climb is.
There are several different approaches to rock climbing, depending on the terrain and conditions and on the proclivities of the climber. These range from solo climbing, which is performed without protection, a minimum of equipment, and no rope, to technical climbing, which makes extensive use of ropes, slings, and mechanical devices for providing extra hand/foot holds and a means of limiting the damage in the event of a fall.
For more information on the styles and techniques of rock climbing, see the articles on climbing and protection.