The Human Development Index (HDI) is a composite statistic used to measure a country's overall development. It considers three key dimensions: life expectancy at birth, education level (measured by mean years of schooling and expected years of schooling), and per capita income. By combining these factors, HDI provides a broader understanding of human well-being beyond just economic performance. Countries are ranked on a scale from 0 to 1, with higher values indicating better development. The HDI helps policymakers identify areas for improvement and compare development levels across nations, making it a valuable tool for assessing progress in human development initiatives.