This realm consists of all water bodies, including the vast oceans, lakes, seas, rivers and ponds. They cover 71 per cent of the earth’s surface. The oceans are large salt water bodies separated by continents. The largest and deepest ocean is the Pacific. Its deepest point is the Mariana Trench about 11,022 meters in depth. This ocean fills the gap between Asia and Australia on the west and America on the east.

The Atlantic Oceans is an ‘S’ shaped water body between the America on the west, and Europe and Africa on its east. Its waters enter through the narrow strait of Gibraltar into the Mediterranean Sea which separates Africa from Europe. A strait is a narrow neck of water between two landmasses that join two water bodies. The Indian Ocean is located at the head of the Indian subcontinent. It stretches from the edge of Africa to Australia in the east.

Lakes are small water bodies surrounded by land while others of larger size are called seas, e.g. Caspian Sea, Aral Sea and Dead Sea. Locate them in your atlas. Apart from seas there are gulfs and bays. A gulf is a body of water jutting deep into the land e.g. Persian gulf and Gulf of Guinea while a bay is an inlet of the sea wider than a gulf, e.g. Bay of Bengal and Bay of Biscay.