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="Flood_Algorithm_-_Formula_2.gif" />
  </query-continue>
  <query>
    <pages>
      <page pageid="149" ns="6" title="File:20140103 211505.jpg" />
      <page pageid="116" ns="6" title="File:Architecture.png" />
      <page pageid="127" ns="6" title="File:Blur dialog1.png" />
      <page pageid="128" ns="6" title="File:Blur dialog2.png" />
      <page pageid="129" ns="6" title="File:Blur select.png" />
      <page pageid="104" ns="6" title="File:Dave Neary.jpg" />
      <page pageid="75" ns="6" title="File:Depth of control point.png" />
      <page pageid="134" ns="6" title="File:Developer-left.png" />
      <page pageid="135" ns="6" title="File:Developer-right.png" />
      <page pageid="176" ns="6" title="File:Flood Algorithm - Formula 1.gif" />
    </pages>
  </query>
</api>