The document discusses the hydrosphere, which is the total amount of water on Earth including oceans, ice, freshwater, and water vapor. It describes the major components of the hydrosphere like oceans, glaciers, freshwater, and atmospheric water vapor. Tables provide data on the volumes and percentages of total water contained in oceans, ice, underground aquifers, lakes, and the atmosphere. The document also outlines the different zones of the oceans from the epipelagic zone at the surface to the deepest hadalpelagic zone, and notes some characteristic animals found in each zone.