Demography is the study of

Demography is the study of human population.

Explanation:

Demography studies most if not all aspects about human population. It checks births, death, sex, migration, etc. and in turn, when we describe the population, it is normally from pertaining to demographic. Demography is also involved in other disciplines such as sociology, economics, statistics, etc.

Through demographics, the necessary departments get to understand people and their needs better. Countries economic decisions is one example that depends on demographic studies. It also affects other areas such as the planning, labor markets analysis, and etc.

Demography is the study of populations.

Everything from like race and ethnicity, to religion, to age distribution, to income distribution and there are many more.

All of those things I have mentioned above can all fall under demography.