UML 2.0 link

Diagram	Description	Learning Priority
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.	High
Class Diagram	Shows a collection of static model elements such as classes and types, their contents, and their relationships. See UML Class diagram guidelines.	High
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.	Low
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.	Medium
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.	Low
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.	Medium
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.	Low
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.	Low
Package Diagram	Shows how model elements are organized into packages as well as the dependencies between packages. See Package diagram guidelines.	Low
Sequence Diagram	Models the sequential logic, in effect the time ordering of messages between classifiers. See UML Sequence diagram guidelines.	High
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.	Medium
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.	Low
Use Case Diagram	Shows use cases, actors, and their interrelationships. See UML Use case diagram guidelines.	Medium

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