The people known as Swahili (sing. Mswahili, pl. Wa Swahili) live along the narrow East African coastline and the adjacent islands (Zanzibar, Pemba, and Mafia) between southern Somalia and northern Mozambique; they also live in the Aomoro Islands and northwestern Madagascar, and there are Swahili settlements in the far African interior near Lake Tanganyika. On the coast, they live in distinct settlements within approximately 2 kilometers of the seas, placed on creeks and on the leeward sides of the many small islets that are protected from the Indian Ocean. Their language, KiSwahili, with its many dialects, belongs to the Sam Family of North-eastern Bantu and has many loanwords from Arabic. It has long been used in a debased form as a lingua franca throughout eastern Africa. It was traditionally written in Arabic script but today Roman script is mostly used. The name "Swahili" comes from the Arabic swahili ("coast" or "margin"). The term was first used to refer to the eighteenth-century coast dwellers by the colonial rulers of the time, the Omani of the sultanate of Zanzibar; they prefer to use the names of their local settlements, such as Mvita (Mombasa), Unguja Zanzibar, or Amu (Lamu). "Swahili" is essentially the name others have given them. They number between 200,000 and 400,000, censuses being unreliable because self-designations have varied from one period to another.