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>
    <querypage qpoffset="10" />
  </query-continue>
  <query>
    <querypage name="Ancientpages">
      <results>
        <page value="20060811084227" timestamp="2006-08-11T08:42:27Z" ns="0" title="Dominio público" />
        <page value="20060812003933" timestamp="2006-08-12T00:39:33Z" ns="0" title="Dragon Data" />
        <page value="20060819231817" timestamp="2006-08-19T23:18:17Z" ns="0" title="Edenspring" />
        <page value="20061008222520" timestamp="2006-10-08T22:25:20Z" ns="0" title="Centronics 14" />
        <page value="20061012141305" timestamp="2006-10-12T14:13:05Z" ns="0" title="Logotipo" />
        <page value="20061013233720" timestamp="2006-10-13T23:37:20Z" ns="0" title="Hitachi Personal Workstation 2020" />
        <page value="20061014102153" timestamp="2006-10-14T10:21:53Z" ns="0" title="Hitachi Creative Workstation 2050" />
        <page value="20061014152943" timestamp="2006-10-14T15:29:43Z" ns="0" title="Visual FoxPro" />
        <page value="20061015004159" timestamp="2006-10-15T00:41:59Z" ns="0" title="Compilador Harbour" />
        <page value="20061015191850" timestamp="2006-10-15T19:18:50Z" ns="0" title="XBase" />
      </results>
    </querypage>
  </query>
</api>