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>
    <pages>
      <page pageid="4142" ns="6" title="File:Nav controllers2.jpg" contentmodel="wikitext" pagelanguage="en" touched="2014-06-26T19:50:10Z" lastrevid="12441" counter="37" length="0" new="" />
      <page pageid="4143" ns="6" title="File:Nav interfaces2.jpg" contentmodel="wikitext" pagelanguage="en" touched="2014-06-26T19:50:10Z" lastrevid="12442" counter="36" length="0" new="" />
      <page pageid="4144" ns="6" title="File:Nav ipcameras2.jpg" contentmodel="wikitext" pagelanguage="en" touched="2014-06-26T19:50:10Z" lastrevid="12443" counter="47" length="0" new="" />
      <page pageid="4145" ns="6" title="File:Nav modules2.jpg" contentmodel="wikitext" pagelanguage="en" touched="2014-06-26T19:50:10Z" lastrevid="12444" counter="58" length="0" new="" />
      <page pageid="4146" ns="6" title="File:Nav receptacles2.jpg" contentmodel="wikitext" pagelanguage="en" touched="2014-06-26T19:50:10Z" lastrevid="12445" counter="59" length="0" new="" />
      <page pageid="4147" ns="6" title="File:Nav security2.jpg" contentmodel="wikitext" pagelanguage="en" touched="2014-06-26T19:50:10Z" lastrevid="12447" counter="70" length="0" />
      <page pageid="4148" ns="6" title="File:Nav specialty2.jpg" contentmodel="wikitext" pagelanguage="en" touched="2014-06-26T19:50:10Z" lastrevid="12448" counter="64" length="0" new="" />
      <page pageid="4149" ns="6" title="File:Nav switches2.jpg" contentmodel="wikitext" pagelanguage="en" touched="2014-06-26T19:50:10Z" lastrevid="12449" counter="47" length="0" new="" />
    </pages>
  </query>
</api>