About this Online Shopping Use Case Diagram
This UML use case diagram example groups e-commerce functions around the actors that interact with them. Use it to define system scope and user goals before detailing screen behavior or message order. The exact actors and checkout steps should reflect the platform being modeled.
Customer roles and shopping goals
The template distinguishes Customer, New User, and Returning User roles. Their visible goals include viewing items, managing a cart, registering, making a purchase, and checking out. Review whether the role distinctions are necessary for your requirements or whether a single Customer actor is clearer.
- View items
- Add, edit, or delete cart items
- Register as a new user
- Make a purchase and check out
External actors and system boundary
The diagram names authentication and payment-related services, including PayPal, as external actors. An external actor is a role or system outside the modeled boundary that interacts with the system. Keep external services outside the boundary and platform functions inside it; verify provider names and integrations against the target design.
When to use this template
Use a use case diagram to discuss who uses which functions, not to show the chronological steps of checkout or the internal payment protocol. Add or remove use cases to match the product scope. Use a sequence or activity diagram when the team needs to review interaction order, alternate outcomes, or detailed checkout behavior.
FAQs about this Template
- What functions are shown in this online shopping use case diagram?
The template shows viewing items, managing cart items, registering, making a purchase, and checking out, along with customer roles and external service actors.
- Why show an external actor in an e-commerce use case diagram?
An external actor represents a person or system outside the modeled platform that interacts with it, such as an identity or payment service. Keep it outside the system boundary and confirm it is part of the actual design.
- Does this use case diagram show the checkout sequence?
No. It summarizes actors and goals. Use a sequence or activity diagram to show the ordered messages or steps in checkout, including conditional outcomes.
(AI & Web)