the World Ocean.
That ocean can then be divided into different ocean basins, which again can be sub-divided.
An ocean basin's size, shape and features - like islands, trenches, and rift valleys - vary because of the way earth's plates continues to move. Earth's highest peaks, deepest valleys and flattest vast plains are all in the ocean.
The word ocean is from the Greek word Okeanos. Our notion of ocean goes back to the notions of the ancient mythology, imaging the world to be encircled by a great river.
As the ocean covers more than 70% of earth its resources is the largest part of earth's resources.
Yet, we have very little knowledge about the ocean and the life of the ocean. And we are frankly not all that clear on our relationship with the ocean.
Take the the Arctic Ocean - because its resources have been largely unavailable to humans with the ice covering it year-round, the argument of who "owns the North Pole, the floor of the Arctic Ocean, and the right of way on shipping routes" has been mute. That is until now. In April 2010, what is considered the eight Arctic nations that have shore along the Arctic Ocean held a heated meeting on how to determine who owns what of that ocean. The native peoples that have lives along these shores for thousands of years were not invited to take past in the negotiations!
In reality its state affects everyone of use in the long run and on a daily basis.
The ocean is connected to major lakes, watersheds, and waterways because all major watersheds on earth drain to the ocean! In that way it can be said that every person on earth has a stake in the world ocean. All of us have part in both how we use the ocean - and how we care for it!
Human development and activity leads to pollution and physical modifications, like changes to beach shores and river as we develop land around it. Also, already now, humans have removed most of the large vertebrates, like whales, from the ocean. Opposite we can also make choices that protect and restore the ocean for generations to come!