What is a "bill"?

A bill is a prominent feature found in many bird species, serving as their primary tool for feeding and manipulation. It is a specialized structure composed of a hard, keratinous covering that forms the upper and lower parts of the beak. The bill varies in shape and size across different bird species, with adaptations that reflect their specific feeding habits. It may be slender, pointed for probing into flowers or crevices, or stout and hooked for tearing prey apart. The bill plays a crucial role in capturing, manipulating, and consuming food, as well as in other important functions such as preening feathers, building nests, and communicating through vocalizations.