Fish have been studied by biologists for centuries, in what is called ichthyology. For more details refer to the Ichthyology category.
Most fish that anglers catch while fishing are within Actinopterygii, the ray-finned fish. Further information about Fishing can be found in the Fishing category.
Details of the human use of fish as food can be found in the fish as food category
Most fish that aquarists are likely to have kept or seen are in Actinopterygii, the ray-finned fish. Further information on about fishkeeping can be found in the fishkeeping category, and Aquarium article.