- Oceans are vast expanse of water.
- Two-third of Earth is covered by water.
- Seas are water bodies partially or fully enclosed by land.
Five oceans of the Earth are:
1. Pacific Ocean
2. Atlantic Ocean
3. Indian Ocean
4. Southern Ocean
5. Arctic Ocean
Imporatance of Ocean
- Oxygen supply: Ocean produces overhalf of the world's oxygen. It absorbs 50 times more carbon dioxide than our atmosphere.
- Climate regulation: Ocean covers 70 per cent of the Earth's surface, thereby transporting heat from the equator to the poles through ocean currents, regulating our climate and weather patterns.
- Transportation: Right from historical times, Oceans serves as an important means of transport.
- Recreation: Beaches serves as a recreational spot attracting millions of tourists.
- Economic benefits: Marine shipping contributes significantly to the employment generation and also to GDP.
- Food: Ocean serves as a source of livelihood for millions of people, right from small fishermen to fish factories (in Japan).
- Medicine: Ocean provides many medicinal products, including ingredients that help fight Cancer, Arthritis, Alzheimer's disease, and Heart disease.