This document discusses different systems of social stratification including slavery, caste systems, estates, and social classes. It compares the views of Marx and Weber on what determines social class and contrasts functionalist and conflict views on why social stratification is universal. The document also analyzes social stratification in different countries and regions globally, how colonialism and world systems theory explain global stratification, and how neocolonialism, multinational corporations, and technology help maintain unequal global stratification despite existing strains in the current system.