Salmon is an oily fish that’s typically classified by the ocean in which it is located. In the Pacific, they are considered part of the genus Oncorhynchus, and in the Atlantic, they belong to the genus Salmo.
There is only one migratory Atlantic species, but five existing species of Pacific salmon: Chinook (or king), sockeye (or red), coho (or silver), pink and chum. In the UK, the main source of salmon is from Scotland, although other varieties are available.