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>
    <backlinks gblcontinue="0|Main_Page|3990" />
  </query-continue>
  <query>
    <pages>
      <page pageid="988" ns="0" title="London Tier2" contentmodel="wikitext" pagelanguage="en" touched="2024-04-17T17:36:09Z" lastrevid="21539" counter="38770" length="1282" />
      <page pageid="3487" ns="0" title="CERN@school" contentmodel="wikitext" pagelanguage="en" touched="2019-02-22T21:10:01Z" lastrevid="19574" counter="9369" length="1315" />
      <page pageid="3741" ns="0" title="Grid Storage" contentmodel="wikitext" pagelanguage="en" touched="2018-11-05T15:58:23Z" lastrevid="18854" counter="64397" length="5706" />
      <page pageid="3980" ns="0" title="GridPP - Start Here" contentmodel="wikitext" pagelanguage="en" touched="2015-05-20T13:16:58Z" lastrevid="8539" counter="7281" length="422" />
      <page pageid="3981" ns="0" title="Start Here - I have a grid certificate" contentmodel="wikitext" pagelanguage="en" touched="2015-05-20T13:16:05Z" lastrevid="8535" counter="6037" length="1089" />
      <page pageid="3982" ns="0" title="Start Here - Installing your certificate in your browser" contentmodel="wikitext" pagelanguage="en" touched="2015-05-20T15:43:31Z" lastrevid="8546" counter="3374" length="316" />
      <page pageid="3983" ns="0" title="Start Here - is your user community represented by a Virtual Organisation" contentmodel="wikitext" pagelanguage="en" touched="2019-02-12T19:07:16Z" lastrevid="8563" counter="5547" length="1229" />
      <page pageid="3984" ns="0" title="Start Here - I do not have a grid certificate" contentmodel="wikitext" pagelanguage="en" touched="2015-05-20T14:52:57Z" lastrevid="8542" counter="5259" length="514" />
      <page pageid="3985" ns="0" title="Start Here - Getting a grid certificate from outside of the UK" contentmodel="wikitext" pagelanguage="en" touched="2015-05-20T13:17:46Z" lastrevid="8540" counter="3765" length="441" />
      <page pageid="3989" ns="0" title="Start Here - Getting a grid certificate from the UKCA" contentmodel="wikitext" pagelanguage="en" touched="2021-11-30T13:38:18Z" lastrevid="21102" counter="3422" length="1439" />
    </pages>
  </query>
</api>