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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>
    <allcategories accontinue="Categories_for_deletion" />
  </query-continue>
  <query>
    <allcategories>
      <c size="1" pages="1" files="0" subcats="0" xml:space="preserve">Account-bound Items</c>
      <c size="0" pages="0" files="0" subcats="0" xml:space="preserve">Active Skills</c>
      <c size="0" pages="0" files="0" subcats="0" xml:space="preserve">Ammunition Skills</c>
      <c size="0" pages="0" files="0" subcats="0" xml:space="preserve">AoE Skills</c>
      <c size="4" pages="4" files="0" subcats="0" xml:space="preserve">April Gears</c>
      <c size="2" pages="2" files="0" subcats="0" xml:space="preserve">Archived Custom Quest Guides</c>
      <c size="1" pages="1" files="0" subcats="0" xml:space="preserve">Archived Events</c>
      <c size="4" pages="4" files="0" subcats="0" xml:space="preserve">August Gears</c>
      <c size="0" pages="0" files="0" subcats="0" xml:space="preserve">Bare Handed Skills</c>
      <c size="143" pages="10" files="131" subcats="2" xml:space="preserve">Candidates for deletion</c>
    </allcategories>
  </query>
</api>