Comments Notification
The list of unapproved comments is on admin/content/comment.



Unapproved comments are the comments left from users without the permission of skipping the comment approval, which is given in admin/people/permissions.



In the site where I took this screenshot, authenticated users are allowed to skip the comment approval, which means that any user with an account is able to write a comment without it gets approved before to be visible to every user.