Frogs are amphibians that are cold-blooded vertebrates known for their distinctive ribbit call. They have scale-less skin, webbed feet, and live in a variety of habitats around the world. Frogs go through distinct life cycle stages from egg to tadpole to adult frog. They have over 3,000 different species that vary widely in size, coloration, diet and habitat, such as poison dart frogs, Goliath frogs, and wood frogs.