How does Facebook "block" feature work?

[Ex_Parrot]

I am wanting to block a few people on Facebook so that they won't even know I'm on there (they are not on my friends list). I don't want to hurt feelings by ignoring friend requests. I try to keep my profile very private with a select few on my friends list who I'm close to in real life. The problem is, these people ARE friends with some of my friends. So I am wondering if they will still see what I write on my friends' profiles, notifications, etc.

[Manny]

Anyone "blocked" on Facebook cannot see you profile and anything that you write or tags of you. (They can still see a photo when you are in it, if the photo does not belong to you, but they cannot see the tag of you.)