If you had to draw the boundaries of the Earth's oceans on a map, would you be able to? The answer is no—because there is really only one "world ocean." Oceanographers have divided the world ocean into four principal areas, or basins: the Pacific, Atlantic, Indian, and Arctic Ocean basins. The Atlantic, Indian, and Pacific Ocean basins merge into icy waters around Antarctica. Some oceanographers define this as a fifth ocean, usually called the Antarctic or Southern Ocean basin.

This video focuses on the Atlantic Ocean basin and is taken from the interactive online game, My Ocean. Test your ocean knowledge and learn about the different basins of the world ocean by playing here.

  • The Atlantic Ocean is the second-largest ocean in the world and covers approximately 20% of the Earth's surface.
  • The Atlantic Ocean was named after Atlas, a character from Greek mythology who supported the heavens on his shoulders.
  • The Atlantic Ocean is, on average, the world's saltiest ocean.
  • The Atlantic Ocean is home to the legendary "Bermuda Triangle." Believers in the Bermuda Triangle claim the region—an officially unrecognized area between Miami, Florida; San Juan, Puerto Rico; and the island of Bermuda—is the site of an unusually high number of disappearances of aircraft and ships.
  • The Mid-Atlantic Ridge—the longest mountain range on the planet—extends from north of the Arctic Circle all the way down past the tip of Africa. Most of it is underwater, but some parts of it are visible as islands, such as Iceland, the Azores (an autonomous region of Portugal), and Ascension Island (a British Overseas Territory).
Atlantic Ocean

one of Earth's four oceans, separating Europe and Africa from North and South America.


molten, or partially melted, rock beneath the Earth's surface.

Mid-Atlantic Ridge

underwater mountain range that runs from Iceland to Antarctica.


bird native to the Antarctic.

polar bear

large mammal native to the Arctic.

tectonic plate

massive slab of solid rock made up of Earth's lithosphere (crust and upper mantle). Also called lithospheric plate.


largest marine mammal species.