Editing Unified Modeling Language (section)

=== Modeling ===
It is important to distinguish between the UML model and the set of diagrams of a system. A diagram is a partial graphic representation of a system's model. The set of diagrams need not completely cover the model and deleting a diagram does not change the model. The model may also contain documentation that drives the model elements and diagrams (such as written use cases).

UML diagrams represent two different views of a system model:<ref>Jon Holt Institution of Electrical Engineers (2004). ''UML for Systems Engineering: Watching the Wheels'' IET, 2004, {{ISBN|0-86341-354-4}}. p.&nbsp;58</ref>

* Static (or ''structural'') view: emphasizes the static structure of the system using objects, attributes, operations and relationships. It includes [[class diagram]]s and [[composite structure diagram]]s.
* Dynamic (or ''behavioral'') view: emphasizes the dynamic behavior of the system by showing collaborations among objects and changes to the internal states of objects. This view includes [[sequence diagram]]s, [[activity diagram]]s and [[UML state machine|state machine diagrams]].

UML models can be exchanged among [[UML tool]]s by using the [[XML Metadata Interchange]] (XMI) format.

In UML, one of the key tools for behavior modeling is the use-case model, caused by [[OOSE]]. Use cases are a way of specifying required usages of a system. Typically, they are used to capture the requirements of a system, that is, what a system is supposed to do.<ref>Manuel Almendros-Jiménez, Jesús & Iribarne, Luis. (2007). Describing Use-Case Relationships with Sequence Diagrams. Comput. J.. 50. 116-128. 10.1093/comjnl/bxl053.</ref>