Tanzania is a country in East Africa bordering the Indian Ocean. Neighboring countries include Burundi, Democratic Republic of the Congo, Kenya, Malawi, Mozambique, Rwanda, Uganda, and Zambia. The geography of Tanzania is varied with Lake Victoria in the west, mountains in the northeast and coastal plains. The government system is a republic. The chief of state and head of government is the President. Tanzania has a mixed economy in which there is a variety of private freedom, combined with centralized economic planning and government regulation. Tanzania is a member of the African Union (AU) and African Economic Community (AEC).