Water and oceans- Hydrosphere:

1. The earth is called the Blue Planet. 71% of the earth is covered with water, including rivers, lakes and ponds.
2. Out of this, 97% is found in the ocean and have high amount of salinity, not safe for humans to drink. 
3. Only 3% is available for fresh water. Most of the fresh water is in the form of glaciers in Antarctica. 
4. The five major oceans are the Pacific Ocean, the Atlantic Ocean, the Indian Ocean, the Southern Ocean and the Arctic Ocean.
5. The Pacific Ocean is the largest ocean and has the deepest trench at Mariana Trench depth of 11,022 m below the sea level.
6. The Atlantic Ocean is the second largest Ocean in the world. It is ‘S’ shaped. It is flanked by the North and South Americas on the western side, and Europe and Africa on the eastern side. The coastline of Atlantic Ocean is highly indented. This irregular and indented coastline provides ideal location for natural harbours and ports. From the point of view of commerce, it is the busiest Ocean. 
7. The Indian Ocean is the only ocean named after a country, that is, India. The shape of ocean is almost triangular. In the north, it is bound by Asia, in the west by Africa and in the east by Australia. 
8. The Southern Ocean encircles the continent of Antarctica and extends northward to 60 degrees south latitude. 
9. The Arctic Ocean is located within the Arctic Circle and surrounds the North Pole. It is connected with the Pacific Ocean by a narrow stretch of shallow water known as Bering strait. It is bound by northern coasts of North America and Eurasia.