Similar to many social platforms, learners and instructors can use the "@" symbol plus the name of another member of a board to call that member's attention to a Pin or Comment.
To use this functionality, simply type the "@" symbol and begin typing the name of the person whose attention you want to get. A menu will come up with the members of the board and that list is dynamically filtered to show possibly relevant other members. See below where we have started to type "@Bri" to find a Brian in the class. Click the relevant learner or instructor's name when you see it to select them for the notification. When you finish and post the Pin or Comment, that member of the board will be notified of your content.