Conversations

If you enable class conversations for individual content items, students can discuss the content with you and their classmates. They can ask for help, share sources, or answer questions others have. As the conversation develops, it appears only with the relevant content. Conversations don't appear on the discussions page.

You can enable conversations for these content items:

Documents
Assignments
Group assignments
Tests
Group tests
Offline submissions
Links to teaching tools

Read more ...

Credit to Blackboard Help