Understanding the thirteen diagrams of UML 2.x is an important part of understanding OO development. Although there is far more to modeling than just the UML the reality is the UML defines the standard modeling artifacts when it comes to object technology.
- Activity Diagram
Depicts high-level business processes, including data flow, or to model the logic of complex logic within a system. See UML Activity diagram guidelines. - Class Diagram
Shows a collection of static model elements such as classes and types, their contents, and their relationships. See UML Class diagram guidelines. - Communication Diagram
Shows instances of classes, their interrelationships, and the message flow between them. Communication diagrams typically focus on the structural organization of objects that send and receive messages. Formerly called a Collaboration Diagram. See UML Collaboration diagram guidelines. - Component Diagram
Depicts the components that compose an application, system, or enterprise. The components, their interrelationships, interactions, and their public interfaces are depicted. See UML Component diagram guidelines. - Composite Structure Diagram
Depicts the internal structure of a classifier (such as a class, component, or use case), including the interaction points of the classifier to other parts of the system. - Deployment Diagram
Shows the execution architecture of systems. This includes nodes, either hardware or software execution environments, as well as the middleware connecting them. See UML
Deployment diagram guidelines. - Interaction Overview Diagram
A variant of an activity diagram which overviews the control flow within a system or business process. Each node/activity within the diagram can represent another interaction diagram. - Object Diagram
Depicts objects and their relationships at a point in time, typically a special case of either a class diagram or a communication diagram. - Package Diagram
Shows how model elements are organized into packages as well as the dependencies between packages. See Package diagram guidelines. - Sequence Diagram
Models the sequential logic, in effect the time ordering of messages between classifiers. See UML Sequence diagram guidelines. - State Machine Diagram
Describes the states an object or interaction may be in, as well as the transitions between states. Formerly referred to as a state diagram, state chart diagram, or a state-transition diagram. See UML State chart diagram guidelines. - Timing Diagram
Depicts the change in state or condition of a classifier instance or role over time. Typically used to show the change in state of an object over time in response to external events. - Use Case Diagram
Shows use cases, actors, and their interrelationships. See UML Use case diagram guidelines.
