The Next Stage in Composition -- McIlroy
As XML adoption becomes more widespread across all industries, there's an increasing focus on how to get XML-tagged content beyond the Web and into print. A recent W3C standard, XSL-FO, is an attempt to add formatting capabilities to XML, an attempt to add print formatting to data that was more likely intended primarily for electronic distribution, Web or otherwise.
Imagine how tough it would be if your father was SGML, and your mother was the anarchy of the Internet! What a difficult time you would have trying to find your real purpose in life.
Someone asked me the other day: "Does anyone really think about XML in the context of SGML anymore?" Well they should, because that's clearly where it came from. XML is a pared-down version of SGML.
According to the official 1.0 XML spec, "The Extensible Markup Language (XML) is a subset of SGML that is completely described in this document. Its goal is to enable generic SGML to be served, received and processed on the Web in the way that is now possible with HTML. XML has been designed for ease of implementation and for interoperability with both SGML and HTML."
Family of Standards
As a clear descendent of SGML, XML might logically be thought to be primarily involved with documents and their expression. XSL was one of the original three XML standards. Where did things go wrong? With all of the energy of the Internet and the Web, and all of the mad greed of the late 1990s, before we knew it XML suddenly became primarily an enabler of commercial data transactions. It hardly seemed worth the trouble of expressing this data visually.
Eventually the limitations of HTML began to nag, and Cascading Style Sheets were dropped into the pot to improve graphic expression (on the Web) including that of XML-tagged data.