Estimated native speakers: 60 million
Estimated total speakers: 65 million
Official/de facto official language in: Thailand
Language family: Tai–Kadai - Tai
A brief history:
Thai is divided into four mutually intelligible dialects. Standard Thai, also known as Siamese or Central Thai, is the official language of Thailand, with over 20 million speakers.
Thai developed from the Southern Chinese Tai–Kadai language family and was gradually enriched by Pali, Sanskrit and Old Khmer words and concepts. Linguistically, Thai is related to languages spoken in Myanmar, northern Vietnam, Yunnan, and Laos. Written Thai was introduced by King Ramkamhaeng in the Sukothai period, around 1283 and text from the Sukothai period can still be read today because it Thai writing has changed little since. The script was based on Pali, Sanskrit and Indian alphabets.
Rhythm and tone are very important elements of the Thai language, which has five tones: low, middle, high, ascending, descending. It's a beautiful, unique language that will reward those who make the effort.