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="Das_Entführte_Kind:ja" />
  </query-continue>
  <query>
    <allpages>
      <p pageid="592" ns="0" title="Beispiel-Steckbrief Antonella" />
      <p pageid="1950" ns="0" title="Bildungsstandards Deutsch" />
      <p pageid="637" ns="0" title="Bildungsstandards Mathematik" />
      <p pageid="1583" ns="0" title="Biologie" />
      <p pageid="1581" ns="0" title="Biologie/Schmetterlinge-Quiz" />
      <p pageid="835" ns="0" title="Brauner Bär NA Klasse 3b Mathe 2015" />
      <p pageid="2457" ns="0" title="Bumerang" />
      <p pageid="1135" ns="0" title="Computer-AG" />
      <p pageid="1531" ns="0" title="DaZ" />
      <p pageid="1157" ns="0" title="Das Entführte Kind:bei dem Nachbarn bleiben" />
    </allpages>
  </query>
</api>