This document discusses population and demographics. It begins by defining key terms like population, demography, and census. It then explores why geography is interested in population and how demographers study factors like population distribution, density, growth rates, and movement. Specific topics covered include the evolution of the world's population over time, population densities in different countries, natural population movement through birth and death rates, and migratory movements. Demographic structures like age structure, gender structure, and economic structure are also summarized.