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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>
    <prefixsearch>
      <ps ns="0" title="Meaning Advantages And Examples." pageid="101499" />
      <ps ns="0" title="Meaning Advantages And Instances." pageid="103991" />
      <ps ns="0" title="Meaning And Examples" pageid="101256" />
      <ps ns="0" title="Meaning And Instances" pageid="102459" />
      <ps ns="0" title="Meaning Background Instances Information" pageid="30695" />
      <ps ns="0" title="Meaning Benefits And Examples." pageid="104435" />
      <ps ns="0" title="Meaning Benefits And Instances." pageid="105259" />
      <ps ns="0" title="Meaning Conveniences And Examples." pageid="103114" />
      <ps ns="0" title="Meaning Conveniences And Instances." pageid="110315" />
      <ps ns="0" title="Meaning Examples Characteristics Facts" pageid="31103" />
    </prefixsearch>
  </query>
</api>