The subscription setting in a Moodle forum determines if students will receive email notifications of new postings to the forum. Depending on which subscription option is chosen by the instructor, the student may have additional choices to unsubscribe or subscribe.
The four email subscription modes that can be set by instructors/designers are:
Optional subscription - Participants can choose whether to be subscribed
Forced subscription - Everyone is subscribed and cannot unsubscribe (not recommended)
Auto subscription - Everyone is subscribed initially, but can choose to unsubscribe at any time
Subscription disabled - Subscriptions are not allowed
Instructors/designers will also have links to:
Show/edit current subscribers
Don't track (don't highlight) unread posts
Instructor subscription options
From the Administration block in the forum, an instructor or teaching assistant can:
Change the Email subscription mode
Subscribe to the forum themselves
See or edit the current subscribers
In Moodle 3.2, there will be a check mark next to the selected subscription mode.
Student subscription options
From the Administration block in the forum, a student may be able to (depending on forum settings determined by the instructor or designer):
Subscribe to the forum via email OR Unsubscribe from this forum - The student can start or stop receiving email notification of new postings.
Track unread posts OR Don't track (don't highlight) unread posts - Toggle on and off a column for tracking posts not yet read by the student.