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>
    <links plcontinue="1|0|Breathing_artifact" />
  </query-continue>
  <query>
    <pages>
      <page pageid="1" ns="0" title="Main Page">
        <links>
          <pl ns="0" title="14 &amp; 6 Hz positive bursts" />
          <pl ns="0" title="4 Hz vertex rhythm" />
          <pl ns="0" title="6 Hz spike-and-wave bursts (WHAM and FOLD)" />
          <pl ns="0" title="ACNS STANDARDIZED ICU EEG NOMENCLATURE v2012" />
          <pl ns="0" title="Alpha rhythm" />
          <pl ns="0" title="Angelman syndrome" />
          <pl ns="0" title="Benign Myoclonic Epilepsy in Infancy" />
          <pl ns="0" title="Benign childhood Epilepsy with CentroTemporal Spikes (=BECTS) or Rolandic epilepsy" />
          <pl ns="0" title="Beta rhythm" />
          <pl ns="0" title="Breach rhythm" />
        </links>
      </page>
    </pages>
  </query>
</api>