South East Asia is a sub-region of Asia, consisting of the countries that are geographically south of China, east of India, west of New Guinea and north of Australia. The region lies near the intersection of geological plates, with heavy seismic and volcanic activity. It is located between the Indian Ocean and the Pacific Ocean.
Southeast Asia consists of two geographic regions: Maritime Southeast Asia (Indonesia, Malaysia, Singapore, Philippines, East Timor, Brunei, and Christmas Island); and Mainland Southeast Asia (Cambodia, Laos, Myanmar/Burma, Thailand, Vietnam) which is known as Indochina
Source: Wikipedia
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