Standard Generalized Markup Language (SGML): ISO 8879: 1986

• SGML declaration
  • Says what the delimiters are for the markup elements
  • < and > are chosen for HTML, SGML's default
• Document Type Definition
  • Structure and rules for the document markup
  • See first definition: HTML 1.1
• Document Itself
  • Allowed to drop end tags where meaning understood
  • Tolerant tagging requires intelligent HTML parser

Document Style Semantics and Specification Language (DSSSL): ISO/IEC 10179: 1996

• Separate ISO Standard for styling SGML
• Style Language, basis for CSS
• Object Flow, basis for CSS
• Transformational language, basis for XSLT
• Document Model: how a set of documents relate, basis for <link>
• A Query Language: basis for XQuery