The Borkou-Ennedi-Tibesti (BET) was until 2008 one of the then 18 regions of Chad, its capital being Faya-Largeau.
Chad (تشاد; Tchad), officially the Republic of Chad ("Republic of the Chad"), is a landlocked country in Central Africa.
Daza (also known as Dazaga) is a Nilo-Saharan language spoken by the Daza people inhabiting northern Chad.
Libya (ليبيا), officially the State of Libya (دولة ليبيا), is a sovereign state in the Maghreb region of North Africa, bordered by the Mediterranean Sea to the north, Egypt to the east, Sudan to the southeast, Chad and Niger to the south and Algeria and Tunisia to the west.
Niger, also called the Niger officially the Republic of the Niger, is a landlocked country in Western Africa named after the Niger River.
Nigeria, officially the Federal Republic of Nigeria is a federal republic in West Africa, bordering Benin in the west, Chad and Cameroon in the east, and Niger in the north.
The Nilo-Saharan languages are a proposed family of African languages spoken by some 50–60 million people, mainly in the upper parts of the Chari and Nile rivers, including historic Nubia, north of where the two tributaries of the Nile meet.
The Saharan languages are a small family of languages spoken across parts of the eastern Sahara, extending from northwestern Darfur to southern Libya, north and central Chad, eastern Niger and northeastern Nigeria.
Tebu is a small family of two Saharan languages, consisting of Daza and Teda.
The Toubou, or Tubu (from Old Tebu, meaning "rock people"), are an ethnic group inhabiting northern Chad, southern Libya, northeastern Niger and northwestern Sudan.