Permissions: what level of privacy?

HI there….

Wondering: you mention user permissions but to what extent are users able to see things and not see things?

I want to create private discussions — I would be able to set up users authorized to view these discussions, too. In fact, I would manage the whole process.

What I need to have though, above all else: I do not want private areas to be seen at all. Meaning, not in search. Not even a title that someone can see to click on. For all intents and purposes, any area they have not been given permission to access does not exist. Completely invisible to them, in every sense of the word.

I also want to make sure I can turn off the ability for users to edit their comments or delete their comments. That way, if there are any “shenanigans” on my site, I’ll have a record of it.

Thoughts?