My PHP is really terrible, so i've decided to post my error here.

Please see error and code below. I'm not sure why i am getting this error.

A PHP Error was encountered

Severity: Notice

Message: Undefined variable: content

Filename: listings/index.php

Line Number: 37

```
 <div class="grid_4" id="refreshList"> <!--start MAIN REFRESH LIST-->
    <img src='<?=base_url()?>images/pixel.png' onload="xajax_test_function();"></img>
  </div><!--end MAIN REFRESH LIST-->

  <div class="clear"></div>

  <div class="grid_12"> <!--start MAIN INTRO PAR-->

  </div> <!--end MAIN INTRO PAR-->

  <div class="grid_12" id="div"> <!--start MAIN LISTINGS-->
  <div>
    <?=$content?>
  </div> <!--end MAIN LISTINGS-->

```