The distribution of the population according to the characteristics such as age, sex, marital status, socio-economic status (caste, religion, language, occupation, etc.) and so on is called composition of population. This is the note about the classification of population composition.
Population data are the indicators of the various information of population like birth, death, migration, age, sex, marital status, religion, literacy, language, occupation, etc.
This is the note about sources of population data.
Migration is another process of demography that deals with the change in the size and composition of the population by migrating from one place to another. This is the note about the measures of mortality and migration.