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="440" ns="0" title="Main Page">
        <images>
          <im ns="6" title="File:45 web.jpg" />
          <im ns="6" title="File:ACDC-1.2 Printmodul.jpg" />
          <im ns="6" title="File:CP2104 45.jpg" />
          <im ns="6" title="File:Centipede 45 640.jpg" />
          <im ns="6" title="File:DIL-CY8C3666AXI-052 45.jpg" />
          <im ns="6" title="File:DIL-UC3A-Evalboard 45.jpeg" />
          <im ns="6" title="File:DILAT90USB162 45.jpg" />
          <im ns="6" title="File:DILAT90USB646 45.jpg" />
          <im ns="6" title="File:DIN Rail BUS Auskoppler.jpg" />
          <im ns="6" title="File:DIN Rail BUS Extender.png" />
        </images>
      </page>
    </pages>
  </query>
  <query-continue>
    <images imcontinue="440|DIN_Rail_CPU_10.jpg" />
  </query-continue>
</api>