Use Case Diagram
A use case diagram at its simplest is a representation of a user's interaction with the system that shows the relationship between the user and the different use cases in which the user is involved. A use case diagram can identify the different types of users of a system and the different use cases and will often be accompanied by other types of diagrams as well.
See also
Agile software development
UML Application
Business Case
Fundamental modeling concepts
SysML
Unified Modeling Language
Use case
User story
References
Bibliography
Gemino, A., Parker, D.(2009) "Use case diagrams in support of use case modeling: Deriving understanding from the picture", Journal of Database Management, 20(1), 1-24.
Jacobson, I., Christerson M., Jonsson P., Övergaard G., (1992). Object-Oriented Software Engineering - A Use Case Driven Approach, Addison-Wesley.
Kawabata, R., Kasah, K. (2007). "Systems Analysis for Collaborative System by Use Case Diagram", Journal of Integrated Design & Process Science, 11(1), 13-27.