title: How to implement chat using jQuery, PHP, and MySQL?
body: <p>I have made a chat script using php, mysql and jquery. It uses json to get data from the server. It makes fixed interval requests to the server with the lastly fetched message id to get new messages from the server. But when multiple users will be chatting then thousands and crores of requests will be made to the server within an hour and the hosting people will block it for sure.</p>
  
  <p>Th gmail chat uses socket I think. Because it does not sends fixed interval requests for sure. Could any one of you please give me some sample code or some direction to solve this issue.</p>
  
  <p>Please I need help desperately.</p>
  
  <p>Many thanks in advance. My respect and regards for all.</p>