Oysters are a kind of mollusc that lives in the sea or salty water. Their shell is in two halves like a clam shell, and the oyster can pull it closed. Oysters eat by filtering food from the water that flows over its shell. They live their adult lives stuck to rocks - a young oyster that has just stuck to a rock is called a spat.

Oysters have been eaten for thousands of years. They can be eaten raw, cooked, smoked or as part of another dish like soup.