This Phone UML Activity Diagram depicts a system's behavior by describing the sequence of actions in a process. Flowcharts and activity diagrams are similar in that they show the flow of actions in an activity; however, activity diagrams can also show parallel or concurrent flows and alternate flows. An activity diagram, as shown in the figure below, is associated with a model activity. When you create an activity diagram, it appears in the Diagrams folder in the Project Explorer view and the Models folder as a child element of the owning activity. The diagram editor displays the corresponding activity frame.