You may have an interest in an active discussion in the Discussion Forums but not be ready to participate. Perhaps someone has asked a question for which you would also like to know the answer. If you contribute to a discussion then you will be notified by email when there is an update to that discussion, but what if you haven't contributed but still want to be notified? As part of the discussion forums feature, it is possible to Follow a discussion which will notify you by email when someone replies.
To follow a discussion, click on the title of the discussion to view the full thread then click on Follow in the top right of the page. The button will change to say Following.
If you are no longer interested in a discussion and want to stop receiving updates, click on the button which now says Following. As you hover over it, it will change to say Unfollow.