Demography
The study of human populations and population trends.
Demographer
A scientist in the field of demography.
Immigration
The movement of people into a country or region, from another country or region.
Emigration
The movement of people out of a country or region.
Crude birth rate (CBR)
The number of births per 1,000 individuals per year.
Crude death rate (CDR)
The number of deaths per 1,000 individuals per year.
Net migration rate
The difference between immigration and emigration in a given year per 1,000 people in a country.
Life expectancy
The average number of years that an infant born in a particular year in a particular country can be expected to live, given the current average life span and death rate in that country.
Infant mortality
The number of deaths of children under 1 year of age per 1,000 live births.
Child mortality
The number of deaths of children under age 5 per 1,000 live births.
Environmental justice
The study of the disproportionate exposure to environmental hazards experienced by people of color, recent immigrants and people of lower socio-economic backgrounds; both an academic field and a social movement.
Age structure diagram
A visual representation of the number of individuals within specific age groups for a country, typically expressed for males and females.
Population pyramid
An age structure diagram that is widest at the bottom and smallest at the top, typical of developing countries.
Developing countries
Countries with relatively low levels of industrialization and income.
Developed countries
Countries that have relatively high levels of industrialization and income.
Population momentum
Continued population growth after growth reduction measures have been implemented.
Total fertility rate (TFR)
An estimate of the average number of children that each woman in a population will bear throughout her childbearing years.
Family planning
The regulation of the number or spacing of offspring through the use of birth control.
Replacement-level fertility
The total fertility rate required to offset the average number of deaths in a population in order to maintain the current population size.
Doubling time
The number of years it takes a population to double.
Rule of 70
A method which dictates that by dividing the number 70 by the percentage population growth rate we can determine a population's doubling time.
Theory of demographic transition
A theory that states that a country moves from high to lower birth and death rates as development occurs and that country moves from a preindustrial to an industrialized economic system.
IPAT equation
A conceptual representation of the three major factors that influence environmental Impact: Population of humans, Affluence, Technology.