3. Indian Ocean

The Indian Ocean is the third largest of the world's oceanic divisions, covering approximately 20% of the water on the Earth's surface. It is bounded by Asia—including India, after which the ocean is named on the north, on the west by Africa, on the east by Australia, and on the south by the Southern Ocean.

As one component of the World Ocean, the Indian Ocean is delineated from the Atlantic Ocean by the 20° east meridian running south from Cape Agulhas (South Africa), and from the Pacific Ocean by the meridian of 146°55' east. The northernmost extent of the Indian Ocean is approximately 30° north in the Persian Gulf. The ocean is nearly 10000 km wide at the southern tips of Africa and Australia, and its area is 73556000 km² including the Red Sea and the Persian Gulf.

Island nations within the ocean are Madagascar, Comoros, Seychelles, Maldives, Mauritius, and Sri Lanka. The archipelago of Indonesia borders the ocean on the east.