A comprehensive resource on the essence, complexity, diversity and importance of the inland waters (lakes, ponds, rivers, streams and wetlands) of the Earth. This major reference work summarizes current knowledge and captures the excitement of the subject, from the distribution of water on Earth to properties of water, from the hydrologic cycle to the physics of water movement in lakes and rivers, from the aesthetic values to the problems of water-borne disease, from metabolism of aquatic ecosystems to behavior of aquatic organisms, from pollution to conservation, from diversity of organisms to diversity and cycling of chemicals, and so forth.