<human>: What is the difference between a crow and a raven?
<bot>: The main difference between a crow and a raven is size. A crow is typically around 30–32 cm (12–13 in) in length, while a raven can range from 32–38 cm (13–15 in). Additionally, crows are generally black or dark brown in color with a white head, while ravens are usually gray-black with a red or yellow bill and legs.