This family of fish include the cods, haddocks, pollock, pollack, lings, and whitings. These all have commercial value as food or as a source of high-quality fish meal. Landings of walleye pollock from the Pacifici Ocean and Bering Sea usually exceed six million metric tons annually, the highest for the cod family.

Longliners was once the primary method for catching these fish, but they have since been replaced with much more efficient steam-powered vessels dragging gill nets and trawls. As a result, many species in this family, including the Atlantic cod, Gadus morhua, Pacific cod, Gadus macrocephalus, and North Atlantic haddock, Melanogrammus aeglefinus are suffering from overfishing.

The Pacific herring, Clupea pallasi, is classified in the family Clupeidae, which include pilchards, shads, sardines, and menhaden. The herring has a subspecies in the north Atlantic, Clupea harengus, and is one of the most important species in the family Clupeidae. Herrings occur in dense schools, so they are subject to mass capture. They are used as food for direct human consumption, or ground into fish oil and fishmeal for domestic animal feed and fertilizers.

From an ecological standpoint, herrings are important as converters of plankton into fish flesh, so they form a great food resources for the pelagic predators.

This common name refers to members of the flounder family, and include the arrowtooth flounder, Atheresthes stomias, and rock sole, Pleuronectes bilineatus. Flounders are flatfishes. They have acquired the habit of swimming with the laterally compresed body oriented horizontally instead of vertically. Early in their development, they begin side swimming. An eye migrates from what becomes the bottom side to the "upper side." Direction of eye migration is genetically determined. The side turned toward the bottom is blind and mostly lacks pigmentation. The upper side is generally cryptically colored and capable of color change, allowing some species to camouflage from predators and prey.

Groundfish are important food fishes for humans and other marine organisms. Since they are bottom dwellers, bottom trawling and dredging are commons means of harvest groundfish.