Snakes bodies are covered with scales. Without this protective armor snakes could not move over rough or hot surfaces like tree bark, rocks, and hot desert sand. Their scales are also nearly waterproof and help to keep the water out. Rough belly scales allow the snake to keep their grip on rough branches and to push off of surfaces when they need to move.
Scales are made up of layers of cells stacked one on top of the other. The outer cells are dead and protect the living ones underneath them. A few times every year a snake will shed a layer of dead skin. The cells underneath are then ready to take over as the outer layer.
When a snake is ready to shed it’s eyes get cloudy and it is temporarily blinded. Why? Because snakes eyes do not have eyelids (that is why they do not blink) but instead are covered with a clear scales called 'spectacle' scales. When a snake is ready to shed its old skin it will rub up against a rough surface like a rock to break the skin near the mouth and then slide right out. Just like taking off a sock!