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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>
    <allpages gapcontinue="Top_Linux_Commands_Part_1" />
  </query-continue>
  <query>
    <pages>
      <page pageid="224" ns="0" title="The X-Frame-Options response header" contentmodel="wikitext" pagelanguage="en" touched="2016-04-15T15:16:50Z" lastrevid="886" counter="8571" length="2161" new="" />
      <page pageid="95" ns="0" title="Top 10 lists" contentmodel="wikitext" pagelanguage="en" touched="2014-03-12T16:53:29Z" lastrevid="535" counter="9082" length="487" />
      <page pageid="238" ns="0" title="Top Chmod Command Examples for Beginners" contentmodel="wikitext" pagelanguage="en" touched="2018-05-05T17:51:46Z" lastrevid="938" counter="3215" length="2123" new="" />
      <page pageid="171" ns="0" title="Top Command Line Games - Linux CLI Games" contentmodel="wikitext" pagelanguage="en" touched="2014-04-18T14:14:45Z" lastrevid="668" counter="11739" length="4090" new="" />
    </pages>
  </query>
</api>