The reason SGML isn't found in more places is that it's extremely sophisticated and complex.

CNN: XML for the absolute beginner

SGML, like XML, is a metalanguage -- a language used for defining other languages.

CNN: XML for the absolute beginner

Berners-Lee defined HTML in SGML, the Standard Generalized Markup Language.

CNN: XML for the absolute beginner

Interestingly enough, the first SGML standard was published using an SGML system developed by Anders Berglund at CERN, the organization that, as we have seen, gave us HTML and the Web.

CNN: XML for the absolute beginner

SGML, but it is much easier to use.

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