E-commerce leverages big data for marketing by analyzing consumer behavior, preferences, and purchase history to tailor personalized experiences. By collecting and processing vast amounts of data, businesses can identify trends, create targeted marketing campaigns, and optimize product recommendations. This data-driven approach enhances customer engagement, boosts conversion rates, and drives sales. Additionally, big data analytics helps businesses understand market dynamics and competitive positioning, enabling more informed decision-making. As a result, e-commerce companies can deepen customer relationships and develop strategies that effectively respond to shifting consumer demands.