World-Systems Theory is a sociological perspective that examines the global economic system as a complex network of interdependent countries. Developed by sociologist Immanuel Wallerstein in the 1970s, it categorizes nations into three main groups: core, semi-periphery, and periphery. Core countries are economically advanced and dominate global trade, while peripheral countries are less developed and often exploited for their resources. This theory emphasizes the historical and structural factors that shape global inequalities. It suggests that the economic activities of core nations influence the development of peripheral nations, creating a system where wealth and power are concentrated in certain areas, perpetuating global disparities.