Algeria is a country located in Northern Africa bordering the Mediterranean Sea. It is considered the gateway between Africa and Europe. Neighboring countries include Libya, Mali, Mauritania, Morocco, Niger, Tunisia, and Western Sahara. Algeria is mostly desert with a few mountains and a narrow coastal plain. The government system is a republic. The chief of state and head of government is the President. Algeria has a mixed economic system in which the economy includes a variety of private freedom, combined with centralized economic planning, and government regulation. Algeria is a member of the African Union (AU).