About Lao: Lao language is the official language of Laos. The Lao is also known as Laotian. It is a tonal language of the Tai. The Lao is written in Lao script, which is an Indic origin script. Lao has been strongly influenced by Thai, the national language of Thailand. The Lao is also spoken by the people in the northeast of Thailand. The difference between Lao and the Northeastern Thai is more political than linguistic.