s-domain function calls. A remote function call looks like this: your javascript code insert a "script" html tag to the page you are visiting. The url of this script tag is your remote server. You also send the name of a callback function to the server as a query string parameter. The browser expects the script tag to retrieve some javascript code from your server. The JSON reponse from your can be turned into a proper javascript function call statement by prepending the name of the callback function first 