Friction is a force that resists against two surfaces sliding across each other. The rougher the surfaces are the more friction they will encounter, and the smoother the surfaces the less friction there will be. Friction is a very important force, and many of your day to day activities rely on friction. You walk around easily because of the friction between the ground and your feet. When you are on a low-friction surface like ice you will find it hard to walk, and you are likely to fall over. The man in the picture is able to climb the rope because of the friction between his hands and the rope.