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="49b69030426104fd294a635803a317fc.gif" />
  </query-continue>
  <query>
    <pages>
      <page pageid="51" ns="6" title="File:1.jpg" />
      <page pageid="43" ns="6" title="File:1024px-LG L194WT-SF LCD monitor.jpg" />
      <page pageid="267" ns="6" title="File:1185915.png" />
      <page pageid="12" ns="6" title="File:200px-Wheel mouse.JPG" />
      <page pageid="11" ns="6" title="File:220px-Acer E360 Socket 939 motherboard by Foxconn.svg.png" />
      <page pageid="53" ns="6" title="File:22hd-4.jpg" />
      <page pageid="454" ns="6" title="File:2325-amd-ryzen-5-5600-6.jpg" />
      <page pageid="67" ns="6" title="File:300px-Dot pitch.png" />
      <page pageid="491" ns="6" title="File:3b63cfaf011368dcd465e161efc41b5e.jpg" />
      <page pageid="476" ns="6" title="File:400px-Departamento del Valle del Cauca, Colombia Mapa.png" />
    </pages>
  </query>
</api>