A population is the number of living things that live together in the same place. A city's population is the number of people living in that city. These people are called inhabitants or residents. The population includes all individuals that live in that certain area.
Population density is the average number of people in a place. In areas with a high population density, people live close to each other, such as in a big city. In areas with a low population density, people usually live far away from each other, such as in rural areas out in the countryside.
Population trends [change]
The world population reached seven billion people in 2011. Global population is going up, but the population growth rate is declining all over the world. Currently India has 32 cities with populations above one million. Increasing population leads to higher health care expenditures.
- Earth Science. 1120 South Capital of Texas Highway, Austin, Texas 78746-6487: Holt, Rinehart and Winston. 2001. ISBN 0-03-055667-8.
- Rogers, Peter (2007). Introduction to Sustainable Development, pp. 84-87.