Population applies to the totality of all units of interest in a study or investigation at a given time in a given area.

Population Distribution
The arrangement of the population in space at a given time, that is geographically or among the various types of residential areas.

The comprehensive total count of units of interest at a given time in a given area defined territory/country. Examples of censuses include Population and Housing Census, Agricultural Census, Livestock Census, Census of Business Establishments, etc.

Population Census
This is the process of collecting and processing of basic social, demographic, and economic data for the entire population of the country. It normally takes place every 10 years. In Kenya it takes place every ten years on the night of 24/25 August.