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>
    <allpages gapcontinue="UEFI" />
  </query-continue>
  <query>
    <pages>
      <page pageid="45" ns="0" title="TBW" contentmodel="wikitext" pagelanguage="ja" touched="2015-02-08T03:56:22Z" lastrevid="145" counter="" length="1509" new="" />
      <page pageid="26" ns="0" title="ThinkPad 10" contentmodel="wikitext" pagelanguage="ja" touched="2016-01-17T09:22:15Z" lastrevid="593" counter="" length="7607" />
      <page pageid="102" ns="0" title="ThinkPad 10のリカバリーメディアの作成方法" contentmodel="wikitext" pagelanguage="ja" touched="2015-08-08T06:07:46Z" lastrevid="362" counter="" length="1787" new="" />
      <page pageid="50" ns="0" title="Thunderbirdで返信時に引用部の前から編集する方法" contentmodel="wikitext" pagelanguage="ja" touched="2015-02-14T01:50:18Z" lastrevid="166" counter="" length="1182" new="" />
    </pages>
  </query>
</api>