<P> The term "Southeast Asia" was first used in 1839 by an American pastor Howard Malcolm in his book entitled Travels in South - Eastern Asia . Malcolm only included the Mainland section and excluded the Maritime section in his definition of Southeast Asia . The term was officially used in the midst of World War II by the Allies, through the formation of South East Asia Command (SEAC) in 1943 . SEAC popularised the use of the term "Southeast Asia", although what constituted Southeast Asia in the early days was not fixed, for example the Philippines and a large part of Indonesia were excluded by SEAC while Ceylon was included . However, by the late 1970s, a roughly standard usage of the term "Southeast Asia" and the territories it encompasses had emerged . Although from a cultural or linguistic perspective, the definitions of "Southeast Asia" may vary, the most common definitions nowadays include the area represented by the countries (sovereign states and dependent territories) listed below . </P> <P> Ten of eleven states of Southeast Asia are members of the Association of Southeast Asian Nations (ASEAN), while East Timor is an observer state . Papua New Guinea has stated that it might join ASEAN, and is currently an observer . Sovereignty issues exist over some territories in the South China Sea . </P> <Table> <Tr> <Th> State </Th> <Th> Area (km) </Th> <Th> Population (2016) </Th> <Th> Density (/ km) </Th> <Th> GDP (nominal), USD (2016) </Th> <Th> GDP (PPP) per capita, Int $(2016) </Th> <Th> HDI (2016) </Th> <Th> Capital </Th> </Tr> <Tr> <Th> Brunei Darussalam </Th> <Td> 5,765 </Td> <Td> 423,196 </Td> <Td> 78 </Td> <Td> 10,458,000,000 </Td> <Td> $76,884 </Td> <Td> 0.865 </Td> <Td> Bandar Seri Begawan </Td> </Tr> <Tr> <Th> Cambodia </Th> <Td> 181,035 </Td> <Td> 15,762,370 </Td> <Td> 85 </Td> <Td> 19,368,000,000 </Td> <Td> $3,737 </Td> <Td> 0.563 </Td> <Td> Phnom Penh </Td> </Tr> <Tr> <Th> East Timor </Th> <Td> 14,874 </Td> <Td> 1,268,671 </Td> <Td> 75 </Td> <Td> 2,501,000,000 </Td> <Td> $4,187 </Td> <Td> 0.605 </Td> <Td> Dili </Td> </Tr> <Tr> <Th> Indonesia </Th> <Td> 1,904,569 </Td> <Td> 261,115,456 </Td> <Td> 132 </Td> <Td> 940,953,000,000 </Td> <Td> $11,720 </Td> <Td> 0.689 </Td> <Td> Jakarta </Td> </Tr> <Tr> <Th> Laos </Th> <Td> 236,800 </Td> <Td> 6,758,353 </Td> <Td> 30 </Td> <Td> 13,761,000,000 </Td> <Td> $5,710 </Td> <Td> 0.586 </Td> <Td> Vientiane </Td> </Tr> <Tr> <Th> Malaysia </Th> <Td> 329,847 </Td> <Td> 31,187,265 </Td> <Td> 91 </Td> <Td> 302,748,000,000 </Td> <Td> $27,267 </Td> <Td> 0.789 </Td> <Td> Kuala Lumpur * </Td> </Tr> <Tr> <Th> Myanmar </Th> <Td> 676,000 </Td> <Td> 52,885,223 </Td> <Td> 98 </Td> <Td> 68,277,000,000 </Td> <Td> $5,832 </Td> <Td> 0.556 </Td> <Td> Nay Pyi Daw </Td> </Tr> <Tr> <Th> Philippines </Th> <Td> 343,448 </Td> <Td> 103,320,222 </Td> <Td> 294 </Td> <Td> 311,687,000,000 </Td> <Td> $7,728 </Td> <Td> 0.682 </Td> <Td> Manila </Td> </Tr> <Tr> <Th> Singapore </Th> <Td> 724 </Td> <Td> 5,622,455 </Td> <Td> 7,671 </Td> <Td> 296,642,000,000 </Td> <Td> $90,151 </Td> <Td> 0.925 </Td> <Td> Singapore (city - state) </Td> </Tr> <Tr> <Th> Thailand </Th> <Td> 513,120 </Td> <Td> 68,863,514 </Td> <Td> 127 </Td> <Td> 390,592,000,000 </Td> <Td> $16,888 </Td> <Td> 0.740 </Td> <Td> Bangkok </Td> </Tr> <Tr> <Th> Vietnam </Th> <Td> 331,210 </Td> <Td> 94,569,072 </Td> <Td> 279 </Td> <Td> 200,493,000,000 </Td> <Td> $6,429 </Td> <Td> 0.683 </Td> <Td> Hanoi </Td> </Tr> </Table> <Tr> <Th> State </Th> <Th> Area (km) </Th> <Th> Population (2016) </Th> <Th> Density (/ km) </Th> <Th> GDP (nominal), USD (2016) </Th> <Th> GDP (PPP) per capita, Int $(2016) </Th> <Th> HDI (2016) </Th> <Th> Capital </Th> </Tr>

Which country in the southeast asian realm has the largest population