What are the 3 major group fish and give an example of each?

The three major groups of fish are jawless fish, cartilaginous fish, and bony fish. Jawless fish, such as lampreys, lack jaws and have a simple body structure. Cartilaginous fish, exemplified by sharks, have skeletons made of cartilage instead of bone. Bony fish, the largest group, include species like salmon and possess a hard skeleton made of bone.