Thai is the national and official language of Thailand and the mother tongue of the Thai people, Thailand's dominant ethnic group. Thai is a member of the Tai group of the Kradai language family. The Kradai languages are thought to have originated in what is now southern China, and are linked to the Austroasiatic, Austronesian, or Sino-Tibetan language families. Many words in Thai are borrowed from Pali, Sanskrit and Old Khmer. It is a tonal and analytic language. Thai also has a complex orthography and relational markers. Thai is mutually intelligible with Lao. Standard Thai, also known as Central Thai or Siamese, is the official language of Thailand, spoken by about 65 million people (1990) including speakers of Bangkok Thai (although the latter is sometimes considered as a separate dialect). Khorat Thai is spoken by about 400,000 (1984) in Nakhon Ratchasima; it occupies a linguistic position somewhere between Central Thai and the Isan on a dialect continuum, and may be considered a variant or dialect of either. A majority of the people in the Isan region of Thailand speak a dialect of the Lao language, which has influenced the Central Thai dialect.

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