You are looking at the HTML representation of the XML format.
HTML is good for debugging, but probably is not suitable for your application.
See complete documentation, or API help for more information. 
<?xml version="1.0"?>
<api>
  <query-continue>
    <allimages gaifrom="110a Girly TeenGirl.jpg" />
  </query-continue>
  <query>
    <pages>
      <page pageid="18834" ns="6" title="File:100Episodes.jpg" />
      <page pageid="20198" ns="6" title="File:100px-26,245,0,218-Electronics Outhouse.png" />
      <page pageid="10498" ns="6" title="File:103bkvb.jpg" />
      <page pageid="19489" ns="6" title="File:105b.jpg" />
      <page pageid="19767" ns="6" title="File:107b No Nose Knows.jpg" />
      <page pageid="19768" ns="6" title="File:108a Patty Caper.jpg" />
      <page pageid="19769" ns="6" title="File:108b Plankton&#039;s Regular.jpg" />
      <page pageid="19770" ns="6" title="File:109b The Krabby Kronicle.jpg" />
      <page pageid="8208" ns="6" title="File:10 Happiest Moments.jpg" />
      <page pageid="16187" ns="6" title="File:110a Gary.jpg" />
    </pages>
  </query>
</api>