This document discusses cultural diffusion, which is defined as the process by which cultural traits, ideas, or behaviors are borrowed from one society and adopted by another. It provides everyday examples of items that have diffused across cultures, such as toothbrushes originating in China and buttons in Greece. The document also examines factors that influence the rate and extent of cultural diffusion, methods of diffusion, and examples of historical periods involving significant cultural exchange, such as the Gunpowder Dynasties, Renaissance, Reformation, and age of Exploration.