The major languages of Indonesia are Austronesian. Austronesian is a family of agglutinative languages spoken in the area bounded by Madagascar in the western Indian Ocean and Easter Island in the eastern Pacific Ocean. There is a considerable diversity in the languages used in Indonesia. More then 500 languages-the vast majority are Austronesian, the rest are Papuan and found in parts of Timor, Papua, and Halmahera-have been accounted for. 

Perhaps the central feature of the Indonesian national culture in the late twentieth century was the Indonesian language. Malay was used for centuries as a lingua franca in many parts of the archipelago. The term Bahasa Indonesia, which refers to a modified form of Malay, was coined by Indonesian nationalists in 1928 and became a symbol of national unity during the struggle for independence. Bahasa Indonesia was spoken in more than 90 percent of households in Jakarta, but outside the capital only 10 to 15 percent of the population spoke the language at home. In Javanese areas, only 1 to 5 percent of the people spoke Bahasa Indonesia in the home. Nationwide, however, some 7 million Indonesians used Bahasa Indonesia as a primary language while more than 100 million others used it as a secondary language. In the early 1990s, it was primarily the language of government bureaucracy, schools, national print and electronic media, and interethnic communication. In many provinces, it was the language of communication between Chinese shopkeepers and their non-Chinese patrons.