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 delimitation of the Southern Ocean in 2000. Additionally, it provides details on coral reefs, their structure and growth, and increasing diseases affecting corals. Finally, it outlines the three ocean zones from sunlit to twilight to sunless and the life found in each zone.