The largest country in sub-Saharan Africa, the second-largest in all of Africa (after Algeria), and the 11th-largest in the world. With a population of around 105 million, the Democratic Republic of the Congo is the most populous officially Francophone country in the world, as well as the 4th-most populous country in Africa (after Nigeria, Ethiopia, and Egypt) and the 15th-most populous country in the world. It is a member of the United Nations, Non-Aligned Movement, African Union, and COMESA. Since 2015, the Eastern DR Congo has been the site of an ongoing military conflict in Kivu.

The Democratic Republic of the Congo has been known in the past as, in chronological order

• Congo Free State
• Belgian Congo,
• Republic of the Congo-Léopoldville
• Democratic Republic of the Congo
• Republic of Zaire
• Democratic Republic of the Congo (again, current)

The country's former name, Zaïre, was derived from the name of the Congo River, sometimes called Zaire in Portuguese, which in turn was derived from the Kikongo word nzere or nzadi ('river that swallows all rivers').

The use of Congo seems to have replaced Zaire gradually in English usage during the 18th century and Congo was the preferred English name in 19th-century literature, although references to Zahir or Zaire as the name used by the local population (i.e. derived from Portuguese usage) remained common.