Ray-finned fish are a diverse group of fish characterized by their bony skeletons and fins supported by thin, flexible rays. They belong to the class Actinopterygii, which is the largest class of vertebrates, including over 30,000 species. These fish inhabit various environments, from freshwater rivers to the deep sea, and they play essential roles in aquatic ecosystems. Ray-finned fish have a wide range of body shapes, sizes, and colors, allowing them to adapt to different habitats. Their fins are used for swimming, maneuvering, and stability, making them efficient swimmers. Examples of ray-finned fish include salmon, trout, and tuna.