Moderators - are like shepherds. They are there to enforce the rules, Sheer any bad sheep who step out of line and if their talents extend to coding/designing they will provide support.
Advisors - tbh I'm not sure what their role is but judging from what I have seen they interact with the people of the community, make them feel at home. Think of them as that grandmother waiting for you to visit with tea and biscuits with the potential of a big sloppy kiss,
Super moderators - They have a little more power/privileges. you start eating the greener grass and your likely to get de-hooved, Shipped to the local restaurant if your one of these renegade sheep stepping out of line. They are mainly moderators with higher privileges
Admins - Head Honchos, creme de le creme with a cherry on top. They'll release, possibly maintain the site (as they'll have access to the servers) and ensure everything runs perfectly server end and that the frontend runs without issues.
Site coordinator -
Nobody responded so I'm sure someone else could give a better description.