**UML Tutorials - Herong's Tutorial Examples** - Version 1.01, by Dr. Herong Yang

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.

*Last update: 2014.*

Table of Contents

Introduction of UML (Unified Model Language)

UML Class Diagram and Notations

►UML Activity Diagram and Notations

►Activity Diagram - Action Notation

Activity Diagram - Control Flow Notation

Activity Diagram - Start and Final Notations

Activity Diagram - Decision Notation

Activity Diagram - Merge Notation

Activity Diagram - Fork Notation

Activity Diagram - Join Notation

Activity Diagram - Object Notation

Activity Diagram - Send Signal Notation

Activity Diagram - Accept Event Notation

Activity Diagram - Partition (Swimlane) Notation

Activity Diagram - Frame Notation and Parameters

UML Sequence Diagram and Notations

UML State Machine Diagram and Notations

UML Use Case Diagram and Notations