
Ep #10: Markup Goes Beyond Tags: Rick Jelliffe on Language Markup, Structure & Semantics in XML
From Rule-Breakers by PROPYLON
December 1, 2025 · 1h 17m · Season 1 · Episode 10
About this episode
Rick Jelliffe discusses his influential work in markup languages and the development of XML standards.
Dive into an in-depth conversation with Rick Jelliffe, one of the most influential figures in the world of markup languages and structured data. Rick's contributions to markup and markup standards span from SGML in the 1980s, XML in the Nineties, up to the present day. He brought his extensive expertise in character encoding to the work on the XML standard. This was a pivotal feature of XML, ensuring that multilingualism was baked right into the XML standard itself taking advantage of the Unicode standard. He is perhaps best known as the inventor of the Schematron XML validation language, ingeniously utilizing XPaths to greatly extend what structures/constraints can be automatically validated in XML documents.
People in this episode
Guest: Rick Jelliffe
Topics covered
- markup languages
- structured data
- XML
- character encoding
- multilingualism
- validation languages
Keywords
- SGML
- Unicode
- Schematron
- XPaths
Mentioned in this episode
Products: Schematron, XML
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