Use case

Common card · No. 217261

In both software and systems engineering, a use case is a structured description of a system’s behavior as it responds to requests from external actors, aiming to achieve a specific goal. The term is also used outside software/systems engineering to describe how something can be used. In software (and software-based systems) engineering, it is used to define and validate functional requirements. A use case is a list of actions or event steps typically defining the interactions between a role (known in the Unified Modeling Language (UML) as an actor) and a system to achieve a goal. The actor can be a human or another external system. In systems engineering, use cases are used at a higher level than within software engineering, often representing missions or stakeholder goals. The detailed requirements may then be captured in the Systems Modeling Language (SysML) or as contractual statements.

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