Population structure refers to the composition of a population, typically characterized by factors such as age, sex, and ethnicity. Understanding this structure helps researchers and policymakers analyze demographic trends, predict future population changes, and address social issues. Key tools for studying population structure include population pyramids, which visually represent the distribution of various age groups within a population. This information is crucial for planning resources, such as education and healthcare, and can influence economic development strategies in different regions, including urban and rural areas.