Humans have gotten into the habit of separating the one big, continuous, mysterious body of water that covers the globe into sectors that we call oceans. Historically, there were just four oceans, but we now recognize five different oceans: the Pacific, Atlantic, Arctic, Indian and Southern Oceans. More @Wikipedia
Hover over any link to get a description of the article. Please note that search keywords are sometimes hidden within the full article and don't appear in the description or title.