Seafood is an important source of (animal) protein in many diets around the world, especially in coastal
areas. Semi-vegetarians who consume seafood as the only source of meat are said to adhere to pescetarianism.
The harvesting of wild seafood is usually known as fishing or hunting, while the cultivation and farming of
seafood is known as aquaculture and fish farming (in the case of fish). Most of the seafood harvest is
consumed by humans, but a significant proportion is used as fish food to farm other fish or rear farm
animals. Some seafoods (i.e. kelp) are used as food for other plants (a fertilizer). In these ways, seafoods
are used to produce further food for human consumption. Also, products such as fish oil, spirulina tablets,
fish collagen, chitin are made from seafoods. Some seafood is fed to aquarium fish, or used to feed domestic
pets such as cats. A small proportion is used in medicine, or is used industrially for nonfood purposes
(e.g. leather).