Simon Willison’s Weblog

What is a Polyfill? Useful new term: a Polyfill is “a shim that mimics a future API providing fallback functionality to older browsers”.

Posted 9th October 2010 at 11:48 am

Recent articles

The last six months in LLMs, illustrated by pelicans on bicycles - 6th June 2025
Tips on prompting ChatGPT for UK technology secretary Peter Kyle - 3rd June 2025
How often do LLMs snitch? Recreating Theo's SnitchBench with LLM - 31st May 2025

browsers 84 polyfill 2 remy-sharp 3 recovered 213

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