Throughout Asia, a diverse range of languages are spoken, including members of many language groups as well as isolated ones. Austroasiatic, Austronesian, Caucasian, Dravidian, Indo-European, Afroasiatic, Turkic, Sino-Tibetan, and Kra–Dai are the major language families. The majority, but not all, of these languages have a long history as a written language.