Population density refers to the number of people that are living in a particular measured area of land. The number of people living in a particular area depend on some factors and these factors include climate and resources.
A favourable climate usually attract large number of people, a place that has a favourable weather will be a choice place for people to consider when they are thinking of where to live.
Another factors that determines, the population density of a place is the number and type of resources that are available in that area. A place with a valuable natural resource or other type of resources will attract large number of people. This is one reason why the population density in the cities is always much more than that of the rural areas, due to the fact that, there are many resources available in the cities.