Ocean covers almost three quarters (71%) of the surface of the Earth. This global, interconnected body of salt water is divided by the continents and larger archipelagos into five oceans as follows:
Southern Ocean — in some regions and cultures, including North America and most of Continental Europe, the Southern Ocean is generally not considered an ocean in its own right, and is divided among the Atlantic, Indian and Pacific oceans.
The area of the global ocean is 361 million square kilometres, its volume is 1370 million cubic kilometres, and its average depth 3790 metres. This does not include seas not connected to the oceans, such as the Caspian Sea.
The boundaries between the oceans are set by the International Hydrographic Organization; e.g., the Southern Ocean extends from the coast of Antarctica to 60 degrees south latitude. Smaller regions of the oceans are known as seas, gulfs, straits, etc.