Written by a team of experts, with well over a thousand captioned photos, illustrations, cutaway drawings, and diagrams, this one-volume encyclopedia explains scientific principles, concepts, and facts in an engaging way for readers 9 to adult. It is packed with information about scientific discoveries, principles, and inventions, under headings like Planet Earth, Living Things, Human Biology, Light and Energy, Space and Time, and Conservation and the Environment, while a reference section offers mini-biographies of important scientists, units and conversion tables, a glossary, and an index.