What are population pyramids? How do they help in understanding about the population of a country?

A population pyramid refers to the graphical representation of population composition in a country. It is also called an age-sex pyramid as it diagrammatically presents the number of males and females in a country according to their age groups. In a population pyramid, the total population is divided into various age groups, e.g. 5 to 9 years, 10 to 14 years, etc. For each age group, the percentage of the total population is subdivided into males and females.

The population pyramid allows us to understand the population composition in a country as it shows us the number of dependents in a country along with the percentage that is economically active. Population pyramids also vary in shape which reveals other information like birth rates and death rates allowing for an in-depth study of the population.