Crows' calls are a type of vocalization made by members of the Corvidae family, which includes crows, ravens, and magpies. The term 'caws' is used to describe the loud, harsh sounds that these birds make. Crows' calls can be used for communication between members of the same species, as well as for warning other animals of potential danger. They can also be used to express emotions such as joy or distress. Crows' calls vary in pitch, volume, and duration depending on the context in which they are used.