Fish provides another class of high-protein or tissue building food. As this term is generally understood, it includes both vertebrate fish that is, fish having a backbone such as salmon, cod, shad etc. and many other water animals such as lobsters, crabs, shrimp, oysters and clams.

Fish can usually be purchased at a lower price than many other food items and for this reason possesses an economic advantage over them. Some varieties of fish are sought more than others, the popularity of certain kinds depending on the individual taste or the preference of the people in a particular locality.

As is well known, fish is an extremely perishable food. Therefore, when it is caught in quantities too great to be used at one time, it is preserved in various ways. The preservation methods that have proved to be the most satisfactory are canning, salting and drying, smoking and preserving in various kinds of brine and pickle.

As such methods are usually carried out in the locality where the fish is caught, many varieties of fish can be conveniently stored for long periods of time and so distributed as to meet the requirements of the consumer. This plan enables persons far removed from the Source of supply to procure fish frequently.