Simon Willison’s Weblog

Bit Twiddling Hacks. I’ve never been much of a bit twiddler, but I’ve always felt I should learn.

Posted 2nd November 2007 at 6:49 am

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

binary 5 bits 1 bittwiddling 1 hacks 10 programming 156

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