Ocean

Maps exhibiting the world's oceanic waters. A continuous body of water encircling the Earth, the world (global) ocean is divided into a number of principal areas. Five oceanic divisions are usually recognized: Pacific, Atlantic, Indian, Arctic, and Southern; the last two listed are sometimes consolidated into the first three.

Earth's oceans (World Ocean)
Arctic Ocean Atlantic Ocean Indian Ocean Pacific Ocean Southern Ocean

An ocean (from Greek Ωκεανός, Okeanos (Oceanus)) is a large body of saline water, and a principal component of the hydrosphere. Approximately 71% of the Earth's surface (~3.61 X 10¹⁴ m²) is covered by ocean, a continuous body of water that is customarily divided into several principal oceans and smaller seas.

More than half of this area is over 3,000 metres (9,800 ft) deep. Average oceanic salinity is around 35 parts per thousand (ppt) (3.5%), and nearly all seawater has a salinity in the range of 30 to 38 ppt. Scientists estimate that 230,000 marine life forms of all types are currently known, but the total could be up to 10 times that number.^[1]