Moderate comments shows you all comments submitted by the community members on a particular idea board.
Comments are sorted based on the campaign selected by the members.
To see the comments added by members, Go to: Communities >> Idea Board >> Moderate Comments
Community admin can change the status of the comments posted by the members. It can be set as Active, Pending Approval or Reject.
Community admin receives a notification email on a new idea created or a new comment posted for an idea by the members. Check how to get approval emails for ideas and comments.
Members get a notification after they create a new idea or submit a comment on existing idea.. Once the community admin approves the new idea or comment, the member gets an email with the updated status. Check how to enable email notification.