This Use Case Diagram for E-Commerce Websites is a behavioral diagram summarising e-commerce website activities and user information. It depicts a graphical representation of the behavioral structure of the system. The diagram also includes processes and users or actors. It describes the overall workflow of the e-commerce website using defined symbols. The use case diagram in software engineering depicts an example of adaptive e-commerce behavior. It encapsulates the functionality of the project by incorporating use cases, actors, and their interactions.