![Use case diagrams are UML diagrams describing units of useful functionality (use cases) performed by a system in collaboration with external users (actors). Use case diagrams are UML diagrams describing units of useful functionality (use cases) performed by a system in collaboration with external users (actors).](https://www.uml-diagrams.org/use-case-diagrams/business-use-case-diagram-elements.png)
Use case diagrams are UML diagrams describing units of useful functionality (use cases) performed by a system in collaboration with external users (actors).
![UML Use Case Diagram for Empirical Software Engineering Research Fig. 3... | Download Scientific Diagram UML Use Case Diagram for Empirical Software Engineering Research Fig. 3... | Download Scientific Diagram](https://www.researchgate.net/publication/325814780/figure/fig3/AS:638676405071872@1529283729264/UML-Use-Case-Diagram-for-Empirical-Software-Engineering-Research-Fig-3-describes-the.png)
UML Use Case Diagram for Empirical Software Engineering Research Fig. 3... | Download Scientific Diagram
![uml - Use case diagram where actions are going through a third party system - Software Engineering Stack Exchange uml - Use case diagram where actions are going through a third party system - Software Engineering Stack Exchange](https://i.stack.imgur.com/ZGVs0.png)