How much does blocking someone on facebook do?

[Tom]

If you block someone, you are almost invisible to them. Pictures of you, you don't have to be tagged, on your friends's profiles can be viewed. They cannot search you up, or find you in someone else's friends list. If someone shares your photo or status, they cannot see it.

That blocked person can still view your profile, only if they make another account or use someone else's. it is important to regularly review your privacy settings. You should make it friends only, or even better, create a list with certain people that you trust. Them click custom, and type in the name of your list.

If your friend gives the blocked person their account, they can view it.