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="Ic_action_new.png" />
  </query-continue>
  <query>
    <pages>
      <page pageid="2" ns="6" title="File:Android filechooser1.png" />
      <page pageid="3" ns="6" title="File:Android filechooser2.png" />
      <page pageid="4" ns="6" title="File:Android filechooser3.png" />
      <page pageid="5" ns="6" title="File:EditPunches.PNG" />
      <page pageid="6" ns="6" title="File:Excel csv.PNG" />
      <page pageid="7" ns="6" title="File:Excel example.PNG" />
      <page pageid="8" ns="6" title="File:Excel save as.PNG" />
      <page pageid="9" ns="6" title="File:Ic action add course.png" />
      <page pageid="10" ns="6" title="File:Ic action change course.png" />
      <page pageid="11" ns="6" title="File:Ic action edit.png" />
    </pages>
  </query>
</api>