title: Twiiter like real time response using PHP
body: <p>Can anyone explain how does the real time response works in Twitter ? 
  Like when u search in twitter while viewing the result u get real-time updates saying
  "7 more people tweeted" .
  I have noticed there is no AJAX call being made.
  Can someone tell me how this works and is it possible to implement such a thing using PHP ?</p>