Sequence Diagram
The sequence diagram highlights the chronology of messages exchanged between objects participating in an interaction. These objects are represented in the diagram by their lifelines.
Example of a sequence diagram
The diagram below describes behavior of an automated teller machine:
• Two entry points (represented by lifelines) have a user access check. This check is described in an interaction.
• Depending on the result of the check, either access is refused and the user card is rejected, or door opening is actuated;
• An optional behavior (represented by a combined fragment) can influence door opening.
See:
