Facebook Javascript Sdk "channelurl"

[mrbean]

Does someone know what they mean by "channelURL" in:

<div id="fb-root"></div>
<script>
  // Additional JS functions here
  window.fbAsyncInit = function() {
        FB.init({
          appId   : 'YOUR_APP_ID', // App ID
          channelUrl : '//WWW.YOUR_DOMAIN.COM/channel.html', // Channel File
          status         : true, // check login status
          cookie         : true, // enable cookies to allow the server to access the session
          xfbml   : true  // parse XFBML
        });


        // Additional init code here


  };


  // Load the SDK Asynchronously
  (function(d){
         var js, id = 'facebook-jssdk', ref = d.getElementsByTagName('script')[0];
         if (d.getElementById(id)) {return;}
         js = d.createElement('script'); js.id = id; js.async = true;
         js.src = "//connect.facebook.net/en_US/all.js";
         ref.parentNode.insertBefore(js, ref);
   }(document));
</script>

Does someone have also an example?