XML raises concerns as it gains prominence

XML´s growing implementation has raised several key concerns. First, because they provide considerable information about a document´s content, XML files include much more data than HTML files. This can burden a company´s network, processor, and storage infrastructures. In addition to extensively describing a document´s contents, XML files typically appear in plain text. These factors create security concerns. And many developers may not be cooperating with the effort to transition the Web from HTML to XML via XHTML (Extensible HTML).