Noted educator and author Cathryn Sill uses simple, easy-to-understand language to teach children the basic characteristics of what fish are, how they swim, breathe, and reproduce, and explains the different ways they protect themselves from predators. With beautifully detailed, realistic paintings, noted wildlife illustrator John Sill introduces readers to the diversity of the fish population, from an Arctic char to a porcupine fish. An afterword provides more details, inspiring further learning. This book is ideal for early childhood and elementary units in science, environment, and marine life.