Simon Willison’s Weblog

HTML5 differences from HTML4. Useful guide, collated by Anne van Kesteren.

Posted 16th June 2007 at 12:31 am

Recent articles

JustHTML is a fascinating example of vibe engineering in action - 14th December 2025
OpenAI are quietly adopting skills, now available in ChatGPT and Codex CLI - 12th December 2025
GPT-5.2 - 11th December 2025

anne-van-kesteren 5 html 93 html5 83

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