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="Basic_Tutorial_Lesson_14:_Creating_a_Reusable_Parameterized_Subcircuit_Device" />
  </query-continue>
  <query>
    <allpages>
      <p pageid="4015" ns="0" title="B2.Spice A/D-RF.Spice" />
      <p pageid="8267" ns="0" title="Basic Electromagnetic Theory" />
      <p pageid="8266" ns="0" title="Basic Principles of Physical Optics" />
      <p pageid="8265" ns="0" title="Basic Principles of SBR Ray Tracing" />
      <p pageid="8264" ns="0" title="Basic Principles of The Finite Difference Time Domain Method" />
      <p pageid="8268" ns="0" title="Basic Principles of The Method of Moments" />
      <p pageid="8018" ns="0" title="Basic Tutorial Lesson 10: Building a Shift Register Using D Flip-Flops" />
      <p pageid="8019" ns="0" title="Basic Tutorial Lesson 11: Building a Binary Counter Using JK Flip-Flops" />
      <p pageid="8020" ns="0" title="Basic Tutorial Lesson 12: Analyzing Basic Mixed-Mode Circuits with Logic Gates" />
      <p pageid="8021" ns="0" title="Basic Tutorial Lesson 13: Creating a New Part from Your Analog Circuit" />
    </allpages>
  </query>
</api>