The five oceans are actually one big “world ocean.” This is one of the interesting facts that are explained in this brief but comprehensive nonfiction text. Photographs, maps, and illustrations aptly combine with short text to describe the basics of oceanography. Maps show the oceans and the continents, and explanations are given concerning the equator, the hemispheres, and the four main directions. Several pages contain illustrations of the animals that live in oceans in the sunlit, twilight and midnight zones. Words such as bioluminescence are defined in the text and also found in the glossary.