Being the second largest continent and second most populous in the world, it has an area of about 30,200,000 square kilometers (7,462,583,080 acres). In Latin, 'Africa' means 'scorching sun'. Three quarters of this land has an average temperature of over 20 ºC (68ºF). Almost the whole year is in summer and therefore it has the name of 'tropical continent'. It is inhabited by over 700 ethnic groups and tribes, with a population of about 0.3 billion. Two thirds of its population is black. It possesses the largest desert in the world, the Sahara and the longest river, the Nile. It also boasts the World's second largest fresh water lake, Lake Victoria. Additionally, Africa boasts large mineral, forest, animal and agricultural resources. The continent consists of 46 separate countries or 53 if all island groups are counted.