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 aicontinue="Editable.png" />
  </query-continue>
  <query>
    <allimages>
      <img name="BB.png" timestamp="2011-07-12T18:16:09Z" url="http://wiki.geosteiniger.cl/mediawiki-1.22.7/images/e/e7/BB.png" descriptionurl="http://wiki.geosteiniger.cl/mediawiki-1.22.7/index.php/File:BB.png" ns="6" title="File:BB.png" />
      <img name="CEDEUS_Detailed_Architecture_with_GeoNode_-_single_db.png" timestamp="2013-12-20T20:15:25Z" url="http://wiki.geosteiniger.cl/mediawiki-1.22.7/images/b/b0/CEDEUS_Detailed_Architecture_with_GeoNode_-_single_db.png" descriptionurl="http://wiki.geosteiniger.cl/mediawiki-1.22.7/index.php/File:CEDEUS_Detailed_Architecture_with_GeoNode_-_single_db.png" ns="6" title="File:CEDEUS Detailed Architecture with GeoNode - single db.png" />
      <img name="CEDEUS_Physical_Architecture-central.png" timestamp="2013-11-04T20:33:53Z" url="http://wiki.geosteiniger.cl/mediawiki-1.22.7/images/f/f0/CEDEUS_Physical_Architecture-central.png" descriptionurl="http://wiki.geosteiniger.cl/mediawiki-1.22.7/index.php/File:CEDEUS_Physical_Architecture-central.png" ns="6" title="File:CEDEUS Physical Architecture-central.png" />
      <img name="CEDEUS_Physical_Architecture-multi-server_decentral.png" timestamp="2013-11-04T20:28:43Z" url="http://wiki.geosteiniger.cl/mediawiki-1.22.7/images/5/5d/CEDEUS_Physical_Architecture-multi-server_decentral.png" descriptionurl="http://wiki.geosteiniger.cl/mediawiki-1.22.7/index.php/File:CEDEUS_Physical_Architecture-multi-server_decentral.png" ns="6" title="File:CEDEUS Physical Architecture-multi-server decentral.png" />
      <img name="Dataenrichment_v4_150g.jpg" timestamp="2013-08-09T15:14:29Z" url="http://wiki.geosteiniger.cl/mediawiki-1.22.7/images/2/27/Dataenrichment_v4_150g.jpg" descriptionurl="http://wiki.geosteiniger.cl/mediawiki-1.22.7/index.php/File:Dataenrichment_v4_150g.jpg" ns="6" title="File:Dataenrichment v4 150g.jpg" />
      <img name="Date.png" timestamp="2011-07-12T17:19:11Z" url="http://wiki.geosteiniger.cl/mediawiki-1.22.7/images/e/e0/Date.png" descriptionurl="http://wiki.geosteiniger.cl/mediawiki-1.22.7/index.php/File:Date.png" ns="6" title="File:Date.png" />
      <img name="DayTravel.png" timestamp="2011-07-12T18:14:27Z" url="http://wiki.geosteiniger.cl/mediawiki-1.22.7/images/2/2a/DayTravel.png" descriptionurl="http://wiki.geosteiniger.cl/mediawiki-1.22.7/index.php/File:DayTravel.png" ns="6" title="File:DayTravel.png" />
      <img name="Delete.png" timestamp="2011-08-06T02:00:59Z" url="http://wiki.geosteiniger.cl/mediawiki-1.22.7/images/8/8c/Delete.png" descriptionurl="http://wiki.geosteiniger.cl/mediawiki-1.22.7/index.php/File:Delete.png" ns="6" title="File:Delete.png" />
      <img name="Desktopgis.jpg" timestamp="2011-08-06T01:50:14Z" url="http://wiki.geosteiniger.cl/mediawiki-1.22.7/images/4/4b/Desktopgis.jpg" descriptionurl="http://wiki.geosteiniger.cl/mediawiki-1.22.7/index.php/File:Desktopgis.jpg" ns="6" title="File:Desktopgis.jpg" />
      <img name="DisplayXYData.png" timestamp="2011-07-12T17:23:24Z" url="http://wiki.geosteiniger.cl/mediawiki-1.22.7/images/9/98/DisplayXYData.png" descriptionurl="http://wiki.geosteiniger.cl/mediawiki-1.22.7/index.php/File:DisplayXYData.png" ns="6" title="File:DisplayXYData.png" />
    </allimages>
  </query>
</api>