title: iterating array on refresh
body: <p>How could I go about writing a snippet, that could iterate through array on refresh? 
  Say I have an array with banner links, and I'd like the banner to change to next one when refreshed. There is a lot of solutions to make it random, but I want it to loop through array in order, and go to the first one after last. </p>
  
  <pre><code>var banner = new Array();
   banner[0] = "http://placehold.it/728x90?text=one";
   banner[1] = "http://placehold.it/728x90?text=two";
   banner[2] = "http://placehold.it/728x90?text=three";
   banner[3] = "http://placehold.it/728x90?text=four";
  
   for(var i=0; i &lt; banner.length; i++){
    var img = document.getElementById("imageid");
    img.src = banner[i];
   }
  </code></pre>
  
  <p>This is the code that I currently have, but it's obviously not working. </p>
  
  <p>Thank you in advance</p>