Ducks are birds. They are also called "waterfowls" because they are normally found in places with water like ponds, streams and rivers. They are related to geese and swans. The duck is the smallest of them all. Ducks also have shorter necks and wings and a stout body. They can live from 2-12 years, depending on species.
Ducks have webbed feet, designed for swimming. Their webbed feet act like paddles for the ducks. A duck waddles instead of walk because of its webbed feet. Do you know that the duck's feet cannot feel cold even if it swims in icy cold water ? Well, the reason for this is because its feet has no nerves or blood vessels !!
Another special thing that the duck has is its water-proof feathers. There is a special gland that produces oil near the duck's tail which spreads and covers the outer coat of the duck's feathers, making it water-proof. Beneath the water-proof coat are fluffy and soft feathers to keep the duck warm.