I keep seeing it listed just as "friend data", and no one clarifying that. Does it mean "friends lists", or "the data of the app user's friends profiles"? And

I keep seeing it listed just as "friend data", and no one clarifying that. Does it mean "friends lists", or "the data of the app user's friends profiles"? And in that second case, "the data of the app user's friends visible to the app user", or "as much data as if the friends had installed the app themselves"? Unless it's that final situation, it's exactly how I assumed Facebook scraping worked already.