Cod is also called flounder. Cod belongs to Vertebrate phylum, Vertebrate Subphylum, Main Gate and Coding Order. Cod are mostly cold-water fish living at the bottom of the ocean and in the middle and lower layers of the deep sea, which are widely distributed in the oceans of the world. Among them, there are many world-class important economic fish in Pinctaceae and Haddock, which have high economic value.

Cod is widely distributed in the oceans of the world and originated in the cold water of the North Atlantic from northern Europe to Canada and the eastern United States. At present, the main producing countries are Iceland, Canada, Russia, Norway and Hokkaido. In China, cod is mainly produced in the Bohai Sea, the Yellow Sea and the northern part of the East China Sea. Its main fishing grounds are in the northern Yellow Sea, the east-southeast of Shandong Higher Education, the southern ocean and the southeastern waters of China. It is one of the marine economic fish species produced in the northern coastal areas.

Cod is white, tender, thick, with few thorns, sweet but not greasy, and is the main edible fish in many countries in the world. Cod is rich in nutrients, such as protein, vitamin A, vitamin D, calcium, magnesium, selenium and other nutrients.