fish, any of approximately 34,000 species of vertebrate animals (phylum Chordata) found in the fresh and salt waters of the world. Living species range from the primitive jawless lampreys and hagfishes through the cartilaginous sharks, skates, and rays to the abundant and diverse bony fishes. This guide explores 120 types of fish, offering a clear look at their distinctive features, behaviors, habitats, and ecological roles. Whether you’re a beginner fish enthusiast or an experienced naturalist, these descriptions help you identify and appreciate the variety in the underwater world. Fish are undeniably a healthy food, but they can have high levels of contaminants, too. Save this list of some of the safest fish with the best nutrition profiles. Registered dietitians reveal the 21 best types of fish to eat, including top picks for heart health, diabetics and more. Here's what to know. Instead, there are 3 main classes, groups, or types of fish: bony fish (Osteichthyes), jawless fish (Agnatha), and cartilaginous fish (Chondrichthyes). Fish are the most diverse group among vertebrates, with over 33,000 different types of fish species. The ultimate guide to fishes & fish life, including definition of a fish, fish bodies, types of fish and the life-cycle of a fish. Read on for a complete guide to ichthyology… In this article, you will learn different types of fish names in English with clear pictures, helping kids, students, teachers, and English learners identify, remember, and use these fish names with confidence. Fish are water animals that live in freshwater or saltwater and breathe through gills. Some fish are small and colorful, while others are large and used for food, fishing, or aquarium keeping. Salmon, tuna, goldfish, trout, shark, and catfish are some common examples of different types of fish. Common names of fish can refer to a single species; to an entire group of species, such as a genus or family; or to multiple unrelated species or groups. Ambiguous common names are accompanied by their possible meanings. Fish have been an important natural resource for humans since prehistoric times, especially as food. Commercial and subsistence fishers harvest fish in wild fisheries or farm them in ponds or breeding cages in the ocean.