Page "Indonesian language" Paragraph 2

Most Indonesians, aside from speaking the national language, are often fluent in another regional language ( examples include Javanese, Sundanese and Madurese ) which are commonly used at home and within the local community.

Most formal education, as well as nearly all national media and other forms of communication, are conducted in Indonesian.

In East Timor, which was an Indonesian province from 1975 to 1999, Indonesian is recognised by the constitution as one of the two working languages ( the other being English ), alongside the official languages of Tetum and Portuguese.