What is a "fender" on a boat used for?

A fender is a crucial component used on boats to protect them from damage when docking. It serves as a cushion or buffer between the boat and the dock or another vessel, absorbing the impact that occurs during the mooring process. When a boat is brought alongside a dock or another boat, the fender helps prevent scratches, dents, and other forms of damage that could occur from contact with hard surfaces. By using fenders effectively, boaters can ensure the longevity and appearance of their vessels while also enhancing safety during the docking process.

In contrast, while flotation devices are essential for emergencies, they serve a very different purpose and are not related to docking. Similarly, shades for sun protection and navigational aids play significant roles in boating but do not offer any protective capability against docking-related impacts. Thus, the primary function of a fender is its protective role during docking.