This document discusses demographic environment and data. It defines demography as the scientific study of human populations, including their size, composition, and distribution over time and geography. Demographic data is important for health planning and identifying markets. The key elements of demography are population size, composition by sex and age, and distribution across territories. Demographic data comes from sources like censuses, surveys, and records. It is collected through methods such as observation, interviews, and questionnaires. A growing middle class is significant as it constitutes the largest consumer segment for manufactured goods. The main segments within the middle class are middle class males, females, and teenagers.