Use case
A use case is a description of a situation or interaction in which a system, method, or capability is applied to achieve or support a goal or outcome.
Software Design for Python Programmers
A use case is a named interaction scenario describing a capability that an external actor can perform with a system.
- How it is used
- Connects functional and nonfunctional requirements to user goals, application behavior, and validation.
- How deep it goes
- Defines diagrams and detailed descriptions with actors, conditions, triggers, action paths, outcomes, and constraints, stopping short of implementation.
- Examples
- Uses a book catalogue’s Search Catalogue, Add Book, and Log In Customer interactions as concrete scenarios and diagram labels.
- What you can do after
- Evaluate application behavior against actor goals and requirements, while providing scenarios for functional specification and black-box testing.
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The Design of Web APIs, Second Edition
A use case is a scenario describing a user goal and the interactions needed to achieve it.
- How it is used
- Guides API capability identification by translating user needs into outcomes, steps, and reusable operations.
- How deep it goes
- Defines goals and decomposes steps, then examines alternatives and flow optimization, but defers programming-interface design.
- Examples
- Uses messaging, online shopping, microwave cooking, food delivery, and money-transfer flows to illustrate goals, steps, and operations.
- What you can do after
- Apply it to identify, prioritize, decompose, and validate API capabilities before selecting interface representations.
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Designing Deep Learning Systems: A guide for software engineers
A description of how an actor interacts with a system to achieve a goal.
- How it is used
- Uses stakeholder interactions and application requirements to establish system goals, scope, and architecture.
- How deep it goes
- Develops use cases into stakeholder questions, service boundaries, APIs, and scenario-specific designs, stopping short of formal notation.
- Examples
- Uses dataset ingestion and fetching workflows plus progressively complex prediction-service scenarios.
- What you can do after
- Evaluate/understand which components and capabilities a system needs for concrete users and production scenarios.
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Collaborative Software Design: How to facilitate domain modeling decisions
A use case is a description of interactions between an actor and a system that produce an observable outcome.
- How it is used
- Uses concrete use cases to discover acceptance criteria and constraints at a specific point in a scenario.
- How deep it goes
- Visualizes use cases through concrete examples, stopping at requirements and constraints rather than implementation.
- Examples
- Uses movie-seat reservation, adjacent-seat rules, one-ticket-per-seat constraints, and corridor discovery.
- What you can do after
- Apply it via Example Mapping to surface acceptance criteria and constraints.
The Art of AI Product Development
A use case is a defined situation describing how a person or organization applies a system to accomplish a goal.
- How it is used
- Guides AI opportunity discovery by connecting customer needs, measurable tasks, business impact, and technical feasibility.
- How deep it goes
- Explains selection and validation criteria but stops short of prescribing a complete implementation design.
- Examples
- Uses unclear chatbots, measurable AI tasks, evaluation metrics, edge cases, and user feedback as teaching examples.
- What you can do after
- Evaluate AI opportunities by user need, impact, feasibility, strategic fit, uncertainty, and feedback requirements.
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Lead Developer Career Guide
A description of how an actor interacts with a system to achieve a particular goal.
- How it is used
- Uses use cases to compare client requests with end-user needs during requirements discovery.
- How deep it goes
- Develops use cases through interviews and discrepancy review, but stops short of formal notation or implementation detail.
- Examples
- Uses roles, expected system use, focus-group notes, survey responses, and discrepancies as concrete use-case evidence.
- What you can do after
- Apply use cases by interviewing users, recording mismatches, and discussing requirement changes with the client and project team.
The Well-Grounded Data Analyst
A use case is a specific situation or purpose for which a tool, system, or method is applied.
- How it is used
- Uses purposes to compare AI-tool demand across users, roles, experience levels, and potential product opportunities.
- How deep it goes
- Defines use cases through survey comparisons and stakeholder recommendations, then proposes follow-up cross-tabulation without detailing implementation.
- Examples
- Uses writing code, debugging, codebase discovery, code documentation, testing, collaboration, and project management as contrasting AI purposes.
- What you can do after
- Evaluate AI product opportunities by identifying popular, underserved, and weakly supported user purposes.
Related concepts
- use case diagrampart of · A use case diagram is a UML behavioral diagram depicting actors, use cases, and their externally visible interactions with a system.
- requirementsuses · A requirement is a stated need, capability, quality, condition, or constraint that a system, product, solution, or project is expected to satisfy.
- actorused by · An actor is an independent entity or participant that performs actions, maintains or pursues state or goals, and interacts with other entities or systems.
- stephas part · A step is a discrete, ordered unit of work or action within a process, workflow, procedure, or task.
- operationused by · An operation is an action or computation performed by or through a system, object, or interface, often producing a result or effect.
- serviceimplemented by · A service is a capability or activity provided by an entity to meet the needs of users or other components.
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