On one side, we have the XML/XMLHttpRequest camp. It uses the world-wide XML standard for data. It also involves using the XMLHttpRequest capabilities of most all browsers to retrieve information from a server. We use the XMLHttpRequest object to get XML from our server. So when we say XML in this article we really are talking about both the data format and the data transportation pattern: the two are tightly linked in this area. Due to security concerns, the server has to be in the same domain as the web page.

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