
But How Do It Know
by J. Scott Clark · first published 2009
33mentions
21recommended by
27HN commenters
2010–2025first – last mentioned
78% recommend22% neutral
Why HN recommends it
Plain-English, bottom-up walk from logic gates to RAM, a CPU and simple assembly, with an online CPU simulator. Easy, light read for beginners and non-CS people who want to understand how computers work.
Summarised by Claude from recommending comments
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Non-CS majors who want to dig deeper might enjoy: But How Do It Know? - The Basic Principles of Computers for Everyone http://amazon.com/dp/0615303765
on “6502 simulated at transistor level in Javascript” ↗There is also "But How Do It Know?" by J Clark Scott. It's good for beginners. http://www.amazon.com/But-How-Know-Principles-Computers/dp/0...
on “Fully Functional 1KB Hard Drive in Vanilla Minecraft” ↗"But how Do it Know?" by J. Clark Scott Incredibly simple and elegant explanation of how computers work.
on “Ask HN: What's the best book you read in 2021?” ↗I’d also add the book “But How Do It Know?” from J. Clark Scott as a fantastic primer, building from gates to RAM and CPU, to a simple bootloader and assembly programming. It comes with a CPU simulator on the book’s website so you could make…
on “Ask HN: Best way to learn about computing history?” ↗The book "But How Do It Know? - The Basic Principles of Computers for Everyone" by J Clark Scott. I understand how computers work because of this book.
on “Ask HN: Do you recall any book or course that made a topic finally click?” ↗"But How Do It Know: The Basic Principles of Computing" was a good look at the 1's and 0's that underlie modern computing. http://www.buthowdoitknow.com/
on “Ask HN: What technical book did you buy and read?” ↗I would recommend "But How Do It Know?" by J. Clark Scott.
on “Z80, the 8-bit Number Cruncher (2011)” ↗…Software: https://www.amazon.com/Code-Language-Computer-Hardware-Softw... The Pattern On The Stone: The Simple Ideas That Make Computers Work: https://www.amazon.com/Pattern-Stone-Computers-Science-Maste... But How Do It Know? - The Basic Principles of Computers for Everyone: https://www.amazon.com/But-How-Know-Principles-Computers/dp/... The Elements of Computing Systems: Building a Modern Computer from First Principles:…
on “Ask HN: Programming 101 online course recommendations?” ↗But How Do It Know? J. Clark Scott
on “Ask HN: What is a good book about how computers work?” ↗”But how do it know?" by J. Clark Scott
on “Ask HN: What book should my CS1 students read?” ↗I'm interested in that simulator, it sounds fun! I started reading 'But How Do It Know' a while back; I never finished it but I can say that it was a very fun read. I've heard that 'From Nand to Tetris' [0] is also quite a worthwhile read. A quick look shows that it not only has a link…
on “Ask HN: What are you learning in 2019?” ↗Thanks to the OP for the book reference (But How do it Know? by Scott), I hadn't heard of it. I had the same kind of aha moment with Petzold's Code.
on “Simulating RAM in Clojure” ↗I absolutely love this book. It's very accessible, though perhaps not for younger kids. [But How Do It Know?] (https://www.amazon.com/dp/B00F25LEVC/ref=dp-kindle-redirect?...)
on “Ask HN: Anything Like Carl Sagan's Cosmos for Computer Science?” ↗I think But How Do It Know?[0] is a good read. It takes a similarly straightforward and light-hearted first principles approach to computer systems organization. Highly recommend. [0] - http://www.buthowdoitknow.com/
on “Ask HN: Books Like 'Calculus Made Easy'?” ↗I have to mention "But How Do It Know?" here as well. I came across it from a previous HN discussion and picked up a copy. It's really, really good. And it's a really easy read. http://www.buthowdoitknow.com/
on “Processor Design: An Introduction (1998)” ↗