Simon Willison’s Weblog

Jeffrey Zeldman: XHTML WTF. Reading the comments, it’s scary how many people are totally ill-informed about HTML5 and XHTML5.

Posted 4th July 2009 at 1:22 am

Recent articles

GPT-5: Key characteristics, pricing and model card - 7th August 2025
OpenAI's new open weight (Apache 2) models are really good - 5th August 2025
ChatGPT agent's user-agent - 4th August 2025

education 26 html5 83 jeffrey-zeldman 23 web-standards 45 xhtml 52 xhtml5 2

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