Most Tanzanians speak variations of Bantu languages and dialects. Various languages also have Hamitic or Nilotic origins. Swahili (or Kiswahili) is the official language, as well as the lingua franca, and is understood in most parts of the country, although its usefulness declines toward the west. English, also an official language, is the primary language of commerce, administration, and higher education. Kiunguja, the form of Swahili, and Arabic are widely spoken in Zanzibar. The first language of most people is one of the local languages.