The Vai are a Manden ethnic group that live mostly in Liberia, with a small minority living in south-eastern Sierra Leone. The Vai are known for their indigenous syllabic writing system known as Vai syllabary, developed in the 1820s by Momolu Duwalu Bukele and other Vai elders. Over the course of the 19th century, literacy in the writing system became widespread. Its use declined over the 20th century, but modern computer technology may enable a revival.