Economic development refers to sustained efforts to promote economic health and living standards in a region. It involves initiatives like developing infrastructure, education, health, and environmental sustainability. While economic growth is measured by increases in GDP, development aims for broader social and economic well-being. The concept has evolved since industrialization, and development economics emerged after WWII to study improving conditions in poorer nations. Underdevelopment occurs when resources are not fully utilized, resulting in slower local progress due to internal and external factors.