quick answer.. when you login the site sends a cookie to your machine that lasts 7200secs (2hours). The site will look at the cookie and see if its in range, if it is you are logged in..
But when i login it looks at everyone and if it doesnt get a response it will log you out..

as i have been away for a week and havent been logging in it seems that everyone looks like they are logged in, seeing as confusion is made i am going to change the settings..