It iterates through all the parameters and their arguments passed in the URL...
var url = window.location.toString();
var query_string = url.split('?');
var params = query_string.split("&");
for (var i = 0; i < params.length; i++)
var name = params[i].split("=");
var arg = params[i].split("=");
alert(i+': '+name+' = '+unescape(arg));