Southeast Asia or Southeastern Asia is a subregion of Asia, consisting of the countries that are geographically south of China, east of India, and north of Australia. The region lies on the intersection of geological plates, with heavy seismic and volcanic activity.
Southeast Asia consists of two geographic regions: the Asian mainland, and island arcs and archipelagoes to the east and southeast. The mainland section consists of Cambodia, Laos, Myanmar, Thailand, and Vietnam; the population of which are primarily Tai peoples and Austroasiatic peoples; the dominant religion is Buddhism, followed by Islam. The maritime section consists of Brunei, East Timor, Indonesia, Malaysia, the Philippines, and Singapore. Austronesian peoples predominate in this region; the dominant religion is Islam, followed by Christianity.