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="Ancient archadian warrior.png" />
  </query-continue>
  <query>
    <pages>
      <page pageid="772" ns="6" title="File:200full.jpg" />
      <page pageid="794" ns="6" title="File:4-bar.jpg" />
      <page pageid="314" ns="6" title="File:Aegina.jpg" />
      <page pageid="628" ns="6" title="File:Agd.gif" />
      <page pageid="608" ns="6" title="File:Airlock.jpg" />
      <page pageid="459" ns="6" title="File:Akaali.jpg" />
      <page pageid="432" ns="6" title="File:Alpha.jpg" />
      <page pageid="42" ns="6" title="File:Ancient archadian.jpg" />
      <page pageid="41" ns="6" title="File:Ancient archadian2.png" />
      <page pageid="39" ns="6" title="File:Ancient archadian in snow.png" />
    </pages>
  </query>
</api>