When you register with a name, you can choose for your online 'logged in' status to be hidden from view, or on view (logged in users who are not hidden are shown on the Index page at the bottom: 'users online' it says or similar). When I'm logged it says 'Portia'. If I just choose to visit and not log in, it doesn't show me but counts me as a 'guest'.
I'm not sure why people would want to be 'hidden' here because you can see everything without logging in and therefore be anonymous anyway.
So 'Guest', and to all the other (?) 'Guests' we have here: come on, get yourself a name!

There's nothing to stop you and you don't even have to register: just type the name you want in your posts (making sure it's a name no-one else uses). It's much easier to chat, advise, listen to advice if we can have a vague identity to relate to. One 'Guest' has given me very good advice and I'd like to be able to recognise them - but I can't. Shame! Hope this helps - "Portia"!
PS. Or you can just sign off your 'Guest' posts like bunny does. And I don't know what that 'cup' is, but then I don't watch 'football' either!