Variety of climbing
          shoes. Photo from:
          http://survival-mastery.com/reviews/rock-climbing-gear.html

Variety of climbing shoes.

    Climbing shoes have special rubber soles that increase the friction coefficient. Climbing shoes have rubber of all kinds, and climber chose them based off what they want. The lower the friction coefficient of the rock the higher the friction coefficient of the shoes needs to be. Smooth rock with require soft rubber, and rough rock will use harder rubber.
    Climbers often chose to climb on dry days because water in the air, or on rock will decrease the friction coefficient. Even with soft rubber, a climber will still slip easier because the rubber is smooth until disturbed by rough rock.
    Climbers will also use chalk. Chalk can be used on sweaty hands to increase the friction, and allow the climber to continue up the wall.
    Climbing is often described as, "a battle between gravity and friction".
Photo from: http://survival-mastery.com/reviews/rock-climbing-gear.html