The Khmer language, the national language of Cambodia, is a member of the Mon-Khmer family of languages spoken over vast area of mainland South-East Asia. For centuries, significant minorities speaking Khmer dialects have resided in Thailand, Laos and Vietnam, so that the language is spoken by at least 15 million people in and near Cambodia. Unlike most of the languages in mainland South-East Asia, Khmer has no tones, but compensates for this by having a large number of distinct vowels. Khmer is written in an ancient alphabetic script that has the same Indic origins as the scripts of neighbouring languages.