You are looking at the HTML representation of the XML format.
HTML is good for debugging, but is unsuitable for application use.
Specify the format parameter to change the output format.
To see the non HTML representation of the XML format, set format=xml.
See the complete documentation, or API help for more information. 
<?xml version="1.0"?>
<api>
  <query-continue>
    <allimages gaicontinue="Character_test1.jpg" />
  </query-continue>
  <query>
    <pages>
      <page pageid="230" ns="6" title="File:12 valves.jpg" />
      <page pageid="334" ns="6" title="File:3D graphics - Jesus Christ, Aliens Anels, Gods.jpg" />
      <page pageid="152" ns="6" title="File:Abducted story1.jpg" />
      <page pageid="288" ns="6" title="File:Adding animation1.jpg" />
      <page pageid="289" ns="6" title="File:Adding animation2.jpg" />
      <page pageid="48" ns="6" title="File:Alien abduc1.jpg" />
      <page pageid="25" ns="6" title="File:Alien tex1.jpg" />
      <page pageid="156" ns="6" title="File:Bob.png" />
      <page pageid="286" ns="6" title="File:Character pack1.jpg" />
      <page pageid="287" ns="6" title="File:Character pack2.jpg" />
    </pages>
  </query>
</api>