You are looking at the HTML representation of the XML format.
HTML is good for debugging, but probably is not suitable for your application.
See complete documentation, or API help for more information.
<?xml version="1.0" encoding="utf-8"?>
<api>
  <query>
    <namespaces>
      <ns id="-2">Media</ns>
      <ns id="-1">Special</ns>
      <ns id="0" />
      <ns id="1" subpages="">Talk</ns>
      <ns id="2" subpages="">User</ns>
      <ns id="3" subpages="">User talk</ns>
      <ns id="4">Peyton Hall Documentation</ns>
      <ns id="5" subpages="">Peyton Hall Documentation talk</ns>
      <ns id="6">Image</ns>
      <ns id="7" subpages="">Image talk</ns>
      <ns id="8">MediaWiki</ns>
      <ns id="9" subpages="">MediaWiki talk</ns>
      <ns id="10">Template</ns>
      <ns id="11" subpages="">Template talk</ns>
      <ns id="12">Help</ns>
      <ns id="13" subpages="">Help talk</ns>
      <ns id="14">Category</ns>
      <ns id="15" subpages="">Category talk</ns>
      <ns id="100">Man</ns>
      <ns id="101">Man talk</ns>
    </namespaces>
  </query>
</api>