Learn about messaging with BPMN in this 31-minute tutorial video presented by Niall Deehan, an international consultant at Camunda. Explore starting processes with messages, waiting for external messages, sending messages to and from processes, non-interrupting messages, and when to use Signal Events. Gain insights into building processes, working with message events, implementing Java delegate interfaces, and using logger delegates. Discover techniques for sending and triggering messages effectively. Prior knowledge of Java, REST, Camunda basics, and BPMN fundamentals is recommended for optimal understanding of the content.