What is tagging and how does it work?
When you tag someone, you create a link to their profile. The post you tag the person in may also be added to that person’s timeline. For example, you can tag a photo to show who's in the photo or post a status update and say who you're with. If you tag a friend in your status update, anyone who sees that update can click on your friend's name and go to their profile. Your status update may also show up on that friend's timeline.
When you tag someone, they'll be notified. Keep in mind they may also be notified if they have face recognition turned on. Learn more about how to manage photos on Facebook you haven't been tagged in. Also, if you or a friend tags someone in your post, the post could be visible to the audience you selected plus friends of the tagged person. Learn more about what happens when you create a tag.
Tags in photos and posts from people you aren't friends with may appear in timeline review where you can decide if you want to allow them on your timeline. You can also choose to review tags by anyone, including your friends.