A lens hood is a device used to block stray light from entering the lens of a camera. It can be attached to the front of the lens and is usually made of plastic or metal. Lens hoods are available in a variety of shapes and sizes to fit different lenses.
Lens hoods are important because they can help to improve the quality of your photos. By blocking stray light, lens hoods can help to reduce lens flare and improve contrast. They can also protect your lens from scratches and other damage.