Central Africa is the core region of the African continent which includes Burundi, the Central African Republic, Chad, the Democratic Republic of the Congo and Rwanda. Middle Africa (as used by the United Nations when categorizing geographic subregions) is an analogous term that includes Angola, Cameroon, the Central African Republic, Chad, the Democratic Republic of the Congo, Equatorial Guinea, Gabon, the Republic of the Congo and São Tomé and Príncipe. All of the states in the UN subregion of Middle Africa, plus those otherwise commonly reckoned in Central Africa (11 in total), constitute the Economic Community of Central African States (ECCAS). Since its independence in 2011, South Sudan has also been commonly included in the region.
The introductory paragraph uses material from the Wikipedia article "Central Africa" as of 5 Nov 2018, which is released under the Creative Commons Attribution-Share-Alike License 3.0.