Blocking a user prevents them from messaging you or sending friend requests.
While blocked users may still see your messages in shared public servers, depending on server settings, blocking stops direct interaction. You may want to block a user when:
They continue contacting you after being asked to stop.
Their messages feel inappropriate or abusive.
You want to restrict interaction without filing a report.
Once blocked, the user is immediately prevented from contacting you, and you can manage or remove blocks at any time.