Activity Diagram - Action Notation

UML Tutorials - Herong's Tutorial Examples

∟Activity Diagram - Action Notation

This section describes the Action Notation used in a UML Activity Diagram. An Action Notation represents an action which is the fundamental unit of behavior specification.

An Action Notation is the primary graphical notation used in a UML Activity Diagram to represent an action, which is the fundamental unit of behavior specification.

An Action Notation is drawn as a rectangle shape with strongly rounded corners. The action name is printed inside the shape. For example, the "Keep Dreaming" action can be drawn as an Action Notation in a UML activity diagram as shown below:

Note that in some UML drawing tools, the Action Notation is called Action State notation and drawn as a shape with straight top and bottom and convex arcs on the two sides.