![4.4 Dependencies :: Chapter 4. Use-Case Diagrams :: Part II: Structural Modeling :: Learning UML :: Programming :: eTutorials.org 4.4 Dependencies :: Chapter 4. Use-Case Diagrams :: Part II: Structural Modeling :: Learning UML :: Programming :: eTutorials.org](http://etutorials.org/shared/images/tutorials/tutorial_8/Luml_0405.gif)
4.4 Dependencies :: Chapter 4. Use-Case Diagrams :: Part II: Structural Modeling :: Learning UML :: Programming :: eTutorials.org
![4.4 Dependencies :: Chapter 4. Use-Case Diagrams :: Part II: Structural Modeling :: Learning UML :: Programming :: eTutorials.org 4.4 Dependencies :: Chapter 4. Use-Case Diagrams :: Part II: Structural Modeling :: Learning UML :: Programming :: eTutorials.org](http://etutorials.org/shared/images/tutorials/tutorial_8/Luml_0406.gif)
4.4 Dependencies :: Chapter 4. Use-Case Diagrams :: Part II: Structural Modeling :: Learning UML :: Programming :: eTutorials.org
![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)