Translations:Help:Notifications/Glossary/44/en

The "primary link" is the destination judged to be the most relevant and informative for users following up on a notification. It's where a user will go to if he or she simply clicks on the notification—on the header, body or primary icon. There is no visible label in the notification itself, though a label is displayed in the email version (and on the no-JavaScript version of the special page).