East Africa or Eastern Africa is the easterly region of the African continent, variably defined by geography or geopolitics. In the UN scheme of geographic regions, 20 territories constitute Eastern Africa:
Tanzania, Kenya, Uganda, Rwanda and Burundi - in Central East Africa, are also included in the African Great Lakes region and are members of the East African Community (EAC). Burundi and Rwanda are sometimes also considered to be part of Central Africa.
Djibouti, Eritrea, Ethiopia and Somalia – collectively known as the Horn of Africa.
Comoros, Mauritius and Seychelles – small island nations in the Indian Ocean.
Réunion and Mayotte – French overseas territories also in the Indian Ocean.
Mozambique and Madagascar – often considered part of Southern Africa, on the eastern side of the sub-continent. Madagascar has close cultural ties to Southeast Asia and the islands of the Indian Ocean.
Malawi, Zambia and Zimbabwe – often also included in Southern Africa, and formerly of the Central African Federation.
Egypt, Sudan and South Sudan (newly independent from Sudan)- collectively part of the Nile Valley. Situated in the northeastern portion of the continent, and are often included in Northern Africa.
Cited from: http://en.wikipedia.org/wiki/East_Africa