Transcription: The email example document, albeit very simple, provides a very nice sophisticated user interface. And it's an application in the sense that it's very self-contained. Once the document comes down, the document itself has all the information it needs. So JavaScript can continue to work with the XML document as it exists inside of the HTML page. It doesn't have to go back out to the server and re-query data. So once everything is downloaded, it's available within the browser.
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