title: How to monitor online status of user (real time)
body: <p>i created a small CMS with php and i want to show logged in users if other users are online or offline.</p>
  
  <p>Currently, i only create a query request but this will not update all the time. I want that user see the changes immediatley if something happend on the fly. I'm looking like a solution it's simular to facebook. If someone logged in, than the user is marked as offline.. if he come only, the user see it immediatley.</p>
  
  <p>I'm sure, the best way is to use ajax but i don't know how is the best solution?</p>
  
  <p>Should i create a site which only give a json back will all the status?</p>
  
  <p>I need a little bit advise because i don't know what i have to google too.</p>
  
  <p>Thanks a lot for help :). </p>