Real talk here for a moment, does anyone mind explaining to me how blocking on this site works? And is it effective at all?

Can blocked users view your profile in any capacity or are they fully blocked out of it? Or can they view your profile but just not ask you questions or interact with your posts?

If a person was blocked, would it be obvious / immediately noticeable to them that they are?

Sorry if these are dumb questions I JUST WANT TO MAKE SURE, better to be safe than sorry!