Code: The Hidden Language of Computer Hardware and Software
Code: The Hidden Language of Computer Hardware and Software by Charles Petzoldby Charles Petzold
Hacker ApprovedRanked 3 of 7 computer science books by recommenders
Explains how computers work from wires and switches up to software, and is praised as a delightful classic.
Explains how computers work from wires and switches up to software, and is praised as a delightful classic.
12 people gave an opinion
- recommend it
- 12
- criticize it
- 0
- approval share
- 100%
Recommended in 8 of 13 months
- November 2025: not recommended
- December 2025: recommended
- January 2026: not recommended
- February 2026: not recommended
- March 2026: recommended
- April 2026: recommended
- May 2026: not recommended
- June 2026: recommended
- July 2026: recommended
- August 2026: recommended
- September 2026: recommended
- October 2026: recommended
- November 2026: not recommended (month in progress)
Why it carries the badge
- 12 people recommend itNeeds 10 or more, met.
- Nobody criticizes itNeeds 2 to 1 or better, met.
- Recommended in 8 of 13 monthsNeeds 4 or more, met.
The same three rules apply to every product, and the badge can’t be bought. How the badge works
What people say about it
The reasons people give, with the number of comments that give each one. Open a reason to read what they said.
Why people recommend it
Each mark is one comment
Classic, widely recommended introduction
“Absolutely recommended! For more up to date content, a second edition was published in 2022.”
Comment from 5 Jul 2026 in “Software, from First Principles” “The antidote for that of course is for folks to read Charles Petzold's _Code_”
Comment from 13 Aug 2026 in “Principia Mathematica is modern and insightful” “this book is a classic and worth mentioning”
Comment from 5 Sep 2026 in “Can guitar frets perform multiplication?” Delightful, well-written prose
“without the prose and lyrics it would be a read so dry, it'd rival silica gel beads”
Comment from 16 Dec 2025 in “I'm Kenyan. I don't write like ChatGPT, ChatGPT writes like me” “Even if you know most of what's being discussed it's such a delightful ride.”
Comment from 15 Mar 2026 in “The Appalling Stupidity of Spotify's AI DJ” “a tour de force in technical communication”
Comment from 15 Mar 2026 in “The Appalling Stupidity of Spotify's AI DJ” Builds computing from basic principles
“Explains how to build an 8 bit calculator with wires, switches, and light bulbs and then keeps on going.”
Comment from 30 Jun 2026 in “We Are the Last People Who Know How It Works” “Will fill in knowledge gaps missing from most new people.”
Comment from 28 Aug 2026 in “Ask HN: If I am 16 what should I learn? Which books should read?”
Other computer science books people recommend
The four most recommended other computer science books, with the same counts for each, so you can compare like for like. The tick on each bar marks the 2 to 1 line the badge needs.
| Product | Recommend | Criticize | Approval | Months | Owned | Badge |
|---|---|---|---|---|---|---|
| The Garbage Collection Handbookby Jones, Richard | 16 | 5 | 76% | 4 | — | Approved |
| Beej's Guide to Learning Computer Scienceby Brian Hall | 15 | 2 | 88% | 1 | — | — |
| Code: The Hidden Language of Computer Hardware and Softwareby Charles PetzoldThis page | 12 | 0 | 100% | 8 | — | Approved |
| The Unix-Haters Handbookby Simson Garfinkel | 8 | 1 | 89% | 4 | — | — |
| Codeby Charles Petzold | 7 | 1 | 88% | 5 | — | — |
What people said
11 of the 13 comments that mention it, newest first. Each links to the original comment.
“a classic one, though somehow hard to read - actually I never finished it”
“it completely changed how I view computing”
“this book is a classic and worth mentioning”
“Will fill in knowledge gaps missing from most new people.”
“The antidote for that of course is for folks to read Charles Petzold's _Code_”
“Absolutely recommended! For more up to date content, a second edition was published in 2022.”
“Explains how to build an 8 bit calculator with wires, switches, and light bulbs and then keeps on going.”
“Hopefully, there will never be a time when at least some folks are not reading books such as”
“Even if you know most of what's being discussed it's such a delightful ride.”
“a tour de force in technical communication”
“without the prose and lyrics it would be a read so dry, it'd rival silica gel beads”
Counts come from 1,795,640 Hacker News comments, November 2025 to November 2026. How we count. Report a mistake.