Aquaculture is the farming of aquatic organisms such as fish, mollusks, crustaceans and aquatic plants. It involves organized production in aquatic environments through various methods ranging from extensive to intensive. The objectives of aquaculture include producing nutritious food, generating income and employment, utilizing land and water resources efficiently, and producing ornamental fish. Common aquaculture systems include pond culture, cage and pen culture, and monoculture or polyculture of various aquatic species.