Simon Willison’s Weblog

What are the differences between a vocabulary, a taxonomy, a thesaurus, an ontology, and a meta-model? IA definitions++

Posted 23rd January 2004 at 8:36 pm

Recent articles

My Lethal Trifecta talk at the Bay Area AI Security Meetup - 9th August 2025
The surprise deprecation of GPT-4o for ChatGPT consumers - 8th August 2025
GPT-5: Key characteristics, pricing and model card - 7th August 2025

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