What visual indicator is used for message flows in BPMN?

In BPMN (Business Process Model and Notation), message flows are represented by dashed lines with open arrowheads. This visual distinction is important as it signifies the flow of messages between different entities or participants in a process, as opposed to regular sequence flows which are used to represent the flow of control within a process.

The use of a dashed line helps to visually differentiate message flows from other types of flows, such as sequence flows or association flows, which aids stakeholders in quickly interpreting the processes being modeled. The open arrowhead further emphasizes that these flows represent the exchange of information rather than a direct flow of activities.

Understanding this notation is essential for anyone working with BPMN, as it enhances clarity and communication within process diagrams, ensuring that all participants can easily identify how information is exchanged across different parts of the business process.