Participants in a online forum maybe anonymous, their real names unknown, with no tie even to an online persona. They may pseudonymous,their real names unknown, but with a persistent record of their actions available. Or they may be named,their real names and identity known and verified.
In this section Judith makes a point about how social media allows for people to live different lives than their media presence. Though written in 2004, this hasn't changed a bit. Even while being able to see each others photos and faces, we still have no clue some times who that person may or may not be in real life. I believe it's gotten even worse because it is so easy to believe what others say about themselves on social media.