Käyttötapauskaavion

Käyttötapauskaavio, known in English as a Use Case Diagram, is a behavioral diagram in the Unified Modeling Language (UML) that visually represents the functionality of a system from the perspective of its users. It illustrates the interactions between different actors and the use cases they perform. Actors are typically external entities, such as people, other systems, or devices, that interact with the system. Use cases, on the other hand, describe a specific sequence of actions a system performs to achieve a measurable result for an actor.

The primary purpose of a use case diagram is to capture the functional requirements of a system. It helps stakeholders understand what the system is supposed to do and who will be using it. The diagram consists of a boundary representing the system, actors positioned outside this boundary, and use cases depicted as ellipses within the boundary. Relationships between actors and use cases are shown using association lines. These diagrams are valuable for communication, requirements gathering, and defining the scope of a system. They provide a high-level overview of system behavior, making complex functionalities more accessible and understandable.