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="Beta.png" />
  </query-continue>
  <query>
    <pages>
      <page pageid="156" ns="6" title="File:40px-Historical.png" />
      <page pageid="805" ns="6" title="File:530west6th.jpg" />
      <page pageid="885" ns="6" title="File:A.gif" />
      <page pageid="197" ns="6" title="File:Acap svg.png" />
      <page pageid="844" ns="6" title="File:Alpinesnowboarder.png" />
      <page pageid="959" ns="6" title="File:Ambox clock yellow.png" />
      <page pageid="747" ns="6" title="File:Apple Logo.jpg" />
      <page pageid="814" ns="6" title="File:Askquestion-yel.gif" />
      <page pageid="733" ns="6" title="File:Audacious logo.png" />
      <page pageid="1033" ns="6" title="File:Basic mvc.png" />
    </pages>
  </query>
</api>