| Term | Definition |
| Birth Rate | the amount of births in that area |
| Death Rate | the amount of deaths in that area |
| Demographic Transition | the change from high birth and death rates to low birth and death rates |
| Growth Rate | the change in the total population over time |
| Population Age Structure | A pyramid that shows how the age is distributed through a population |
| Replacement- level Fertility | fertility rate that will replace the population of parents |
| Total Fertility Rate | Avergae number of children born to women |
| Zero Population Growth | when the birth rate equals the death rate |