This UML class diagram illustrates the composition and operation of an e-commerce system. It identifies key entities like customer, order, cart, product, payment, shipment, review, and category. Class relationships define how customers place orders, add products to the cart, and make payments. Customers take and inspect orders, and every product has a specific category. The UML class diagram supports major functionalities like user registration, login, order processing, payment management, and tracking shipment. This UML class diagram enables an effective online shopping system architecture that supports enhanced inventory management, customer interaction, and purchase workflow.