The Indian Ocean is the third largest of the world's five oceans (after the Pacific Ocean and Atlantic Ocean, but larger than the Southern Ocean and Arctic Ocean). The total area of the Indian Ocean is about 73.4 million sq km (about 28.3 million sq mi) and is bounded on the West by Africa, on the North by Asia, on the East by Australia and the Australasian islands, and on the South by Antarctica..
The Indian Ocean contains numerous islands, the largest of which are Madagascar and Sri Lanka.. Smaller islands include the Maldive group and Mauritius. From Africa the ocean receives the waters of the Limpopo and Zambezi rivers, and from Asia those of the Irrawaddy, Brahmaputra, Ganges, Indus, and Shatt al-Arab rivers. As a rule, the winds over the Indian Ocean are gentle, with frequent protracted calms. Hurricanes occur occasionally, however, particularly near Mauritius, and the ocean is notable for its monsoons.
The Indian Ocean provides major sea routes connecting the Middle East, Africa, and East Asia with Europe and the Americas. It carries a particularly heavy traffic of petroleum and petroleum products from the oilfields of the Persian Gulf and Indonesia. Its fish are of great and growing importance to the bordering countries for domestic consumption and export. Fishing fleets from Russia, Japan, South Korea, and Taiwan also exploit the Indian Ocean, mainly for shrimp and tuna. Large reserves of hydrocarbons are being tapped in the offshore areas of Saudi Arabia, Iran, India, and western Australia. An estimated 40% of the world's offshore oil production comes from the Indian Ocean. Beach sands rich in heavy minerals and offshore placer deposits are actively exploited by bordering countries, particularly India, South Africa, Indonesia, Sri Lanka, and Thailand.
CIA World Factbook; The World Almanac, 12/2004