A middle ground between ignoring and blocking
Sometimes blocking feels like too big a step, whether it's someone you know in real life or a situation you'd rather not escalate. Restrict lets you dial down someone's visibility on your account without an obvious, public signal that anything changed.
What the other person actually sees
A restricted account doesn't get a notification and can still view your profile and posts normally, so from their side nothing looks different -- the only change is that their comments and messages become far less visible to you and others.
Frequently Asked Questions
Can a restricted person still see my posts?
Yes -- restricting only limits how visible their comments and messages are; it doesn't hide your profile or posts from them.
Can I undo a restriction later?
Yes, you can go back to that profile at any time and select 'Unrestrict' to reverse it.