Africa is usually said to have 55 countries, which includes the disputed territory of Western Sahara (which is internationally recognized but is occupied by Morrocco). 48 of these countries are located on the mainland of the African contient, while 6 are island nations. It also includes the very new country of Southern Sudan.
The African Union includes 54 of the 55 internationally recognized African countries, with Morocco refusing to join because of the AU`s inclusion of Western Sahara.
There are other de facto nations with their own independently operating governments in Africa, specifically in the place we commonly know as Somalia. Only one government is internationally recognized in Somalia, but 2 de facto nations of Somaliland and Puntland exist in different areas of the country. The only thing that keeps Somaliland and Puntland from being on the political map of Africa is a lack of recognition by other countries. In practical terms, they are independent. This was the situation with South Sudan until its recent independence.
Here are some political Africa maps for your reference.


Update: Here is a 2012 political map of Africa that includes the world`s newest country: Southern Sudan.
















A lot of people have the impression that Africa is all tropical rainforest or all savanna, but Africa displays a lot of climatic variation. Some regions are indeed tropical, but there are high mountain peaks in Africa that are snow-covered much of the year. The northern part of Africa is mostly desert, dominated by the great Sahara Desert. An strip of semi-desert followed by steppe separates the Sahara from sub-saharan Africa, where rainforests, deciduous forests, and savanna plains dominate. More semidesert and steppe is found in South Africa and east Africa, while the Namibian desert is found in southwest Africa.


North Africa is the northernmost region of the African continent, lying north of and on the Sahara Desert. The exact definition of the area varies depending on which authority you ask, but the countries always included are the "Maghreb" countries of Morocco, Algeria, Tunisia, and Libya, plus Egypt. Western Sahara (mostly occupied by Morocco) is usually included, and Sudan is often included as well. Mauritania is sometimes included.




The Arab Republic of Egypt is located in North Africa, with the Sinai Peninsula located in Western Asia (the Suez Canal considered the dividing point between Africa and Asia. It is sometimes included in certain definitions of the Middle East, because of it's partial location in Asia. The Mediterranean Sea lies to the north of Egypt, while it borders Libya to the west, Israel and the Palestinian-controlled Gaza Strip to the northeast, the Red Sea to the east, and Sudan to the south. 


















