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 apcontinue="IBHLink_S5++:S7_PLC_with_IBHLink_S7++" />
  </query-continue>
  <query>
    <allpages>
      <p pageid="110" ns="0" title="Create Variables manually with Intouch" />
      <p pageid="111" ns="0" title="Create Variables with Intouch TagCreator" />
      <p pageid="105" ns="0" title="DCOM Configuration" />
      <p pageid="17" ns="0" title="DCOM configuration" />
      <p pageid="900" ns="0" title="Greengrass" />
      <p pageid="590" ns="0" title="IBHLink:S7++:SINAMICS G120 with IBHLink S7++" />
      <p pageid="593" ns="0" title="IBHLink S5++:Beckhoff TwinCAT PLC with IBHLink S5++" />
      <p pageid="601" ns="0" title="IBHLink S5++:Network configuration via USB" />
      <p pageid="717" ns="0" title="IBHLink S5++:PLC-PLC communication" />
      <p pageid="896" ns="0" title="IBHLink S5++:S7 1500 PLC with IBHLink S7++" />
    </allpages>
  </query>
</api>