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>
    <allpages>
      <p pageid="302" ns="0" title="Beat the Tension - Laugh at Brief Funny Jokes4426308" />
      <p pageid="51" ns="0" title="Fabricating SketchChairs" />
      <p pageid="303" ns="0" title="How Will Hiring Escorts Solutions in London Help You to Enjoy Your Holiday?1413436" />
      <p pageid="262" ns="0" title="Localization" />
      <p pageid="1" ns="0" title="Main Page" />
      <p pageid="304" ns="0" title="Searching For a Tantric Massage2530849" />
      <p pageid="2" ns="0" title="SketchChair Manual" />
      <p pageid="263" ns="0" title="SketchChair Roadmap" />
      <p pageid="52" ns="0" title="SketchChair Tutorials" />
    </allpages>
  </query>
</api>