Note: You are currently viewing documentation for Moodle 3.2. Up-to-date documentation for the latest stable version of Moodle is probably available here: Dialogue module.
Dialogues can be useful when you want a location to give private feedback to students on their online activity. For example, if they are participating in a language forum and have a grammatical error that you want to point out, without embarassing them, a dialogue is the perfect place.
When students initially enroll on a site, you might want to send them a welcome dialogue to let them know you are there. This way if they have something to say to you, they will feel more comfortable responding to you since you made the first step.
The latest version of Dialogue is compatible with Moodle 1.6.x.