Fender damage is a term used to describe the damage that can occur to the fenders of a vehicle. It is usually caused by collisions, but can also be caused by weathering or other environmental factors. The two most common types of fender damage are dents and dings. Dents are indentations in the metal that can be caused by a collision or other impact. Dings are smaller, shallow dents that are usually caused by flying debris or hail.