A fish is any marine creature (including freshwater habitat) that has a backbone and fins. It must be a vertabrate.  There are over 23,000 species of fish in the ocean. Here are a few examples:


The complete list of fishes on this wiki is at

Marine Marine HabitatsAquariumsGlobal OceansOcean Weather
Vertebrate FishesMammalsReptilesAmphibiansCartilaginous FishesSharks
Invertebrate ArthropodMolluscaEchinodermsCnidaria
Conservation Status Critically EndangeredEndangeredNear ThreatenedVulnerableLeast ConcernData DeficientNot Evaluated