Population Concentrations
These are areas where people are together in a cluster. There are five large concentrations:

East Asia
- ΒΌ of world population here
-most of this is from China
-Most of China's population lives near the coast and in the river valleys

South Asia
- bound by the Himalayas and a desert in Pakistan
-1/4th of the world lives in this one as well
-this area includes Pakistan, India and Bangladesh
-most of this is from India
-much of India's population is concentrated along the plains of the Indus and Ganges rivers and the coast lines

Europe
- population is concentrated in cities
-1/9th of the world's population (600-700 million people)

Eurasia has more than half of the world's population (Asia itself being a little over half)


North America
- megalopolis
-A megalopolis (sometimes called a megapolis or megaregion) is typically defined as a chain of roughly adjacent metropolitan areas. The huge metropolitan area along the eastern seaboard of the U.S. extending from Boston, Massachusetts through New York City; Philadelphia, Pennsylvania; Baltimore, Maryland and ending in Washington, D.C (also includes southeast Canada)

Some new texts list southeast Asia as a separate category after Europe instead of the megaolopolis
-Includes the island states of Indonesia and the Philippines
-The island of Java in Indonesia has 100 million people
-This also includes the other island chains and countries in that area of the world
-This works if you do not consider this part of east Asia

Summary
Asia accounts for over 60% of the world population with almost 3.8 billion people. China and India together have about 40 percent of the world's population. Africa follows with 840 million people, 12% of the world's population. Europe's 710 million people make up 11% of the world's population. North America is home to 514 million (8%), South America to 371 million (5.3%), and Australia to 21 million (0.3%).