The document discusses the major bodies of water on Earth including the four oceans - Pacific, Atlantic, Indian, and Arctic. It notes that the Pacific Ocean is the largest and deepest. It also mentions the Southern Ocean, delimited in 2000, located north of Antarctica. Additionally, it provides details about coral reefs, how they form in warm, shallow seas made of coral polyps' skeletons, and how coral diseases have increased dramatically in the past 10 years. Finally, it outlines the three ocean zones - sunlit, twilight, and sunless - and the types of life found in each zone.