Estonian (eesti keel [ˈeːsti ˈkeːl] ) is the official language of Estonia, spoken natively by about 922,000 people in Estonia and 160,000 outside Estonia. It belongs to the Finnic branch of the Uralic language family. One distinctive feature that has caused a great amount of interest among linguists is what is traditionally seen as three degrees of phonemic length: short, long, and "overlong", such that /sɑdɑ/, /sɑˑdɑ/ and /sɑːdɑ/ are distinct. In actuality, the distinction is not purely in the phonemic length, and the underlying phonological mechanism is still disputed.