I'm 17 and wrote this guide on how CPUs run programs

It's also a very good idea to write these types of resources when you teach yourself something new because it clarifies your thought process and helps you identify parts that are still unclear even though you initially thought you understadn them etc.

I also liked this at the end:

""" I talked to GPT-3.5 and GPT-4 a decent amount while writing this article. While they lied to me a lot and most of the information was useless, they were sometimes very helpful for working through problems. LLM assistance can be net positive if you’re aware of their limitations and are extremely skeptical of everything they say. That said, they’re terrible at writing. Don’t let them write for you. """

Congrats, cool project.

>The central processing unit (CPU) of a computer is in charge of all computation. It’s the big cheese. The shazam alakablam. It starts chugging as soon as you start your computer, executing instruction after instruction after instruction.

Given the context, that would read much better as:

>The central processing unit (CPU) of a computer is in charge of all computation. It starts chugging as soon as you start your computer, executing instruction after instruction after instruction.

I’m not super-technical, but I do get paid to write.

Your work here is great. Keep it up!

These sorts of topics are usually well-covered in the matching undergraduate-level computer science courses (computer architecture and operating systems, which, these days, are mostly optional since out of fashion).

Several universities have free courses available, and some of the professors in the field have also written books.

You'll also find pretty informative presentations in the relevant tech conferences if you'd rather stay closer to the state of the art.

Still, teaching is an art that is undervalued, and making the information more available or more fun to interact with is certainly very valuable.

> Apparently everything online about how operating systems and CPUs work is terrible.

Unfortunately finding good information is not easy, but it is out there - you've proven it by synthesizing some of that hard to find information into a better form. My degree is in mathematics, but my computing knowledge is self taught. Knowing how to learn in this way and to be able to communicate highly technical information in an approachable manner are incredibly important skills and not to be underestimated.

I have two links to share - I limited myself to two because we could be here a long time otherwise:

1. https://git.lain.faith/sys64738/airs-notes.git (TOC for linker part here: https://lwn.net/Articles/276782/) - you've scratched the surface of ELFs and linking. This is a 20-article blog series by Ian Lance Taylor plus miscellaneous extra topics containing everything you ever wanted to know about ELFs and quite a bit that will likely make you wonder how any of your commands are actually even working! There's even a brief mention of ELF's companion, DWARF, which amongst other things is a virtual machine used every time a C++ exception is triggered.

2. Have you seen this excellent project? https://0xax.gitbooks.io/linux-insides/content/ - essentially a human-readable walkthrough of how the Linux kernel does stuff. Has almost certainly been shared on HN before.

I usually don’t comment on « I’m xxx years old and did yyy » because I’m not interested in material that would be « good/great for an xxx years old ». In this case, this is great work, period. Adding « for an xxx years old » would be insulting.

Some sections remind me of the material of my college courses, which were quite extensive as my degree historically had a dual electronics/software specialization.

> Apparently everything online about how operating systems and CPUs work is terrible.

Agree with that! As a pro tip, when online resources are scarce for a subject, try adding keywords to find college degree resources (slides, websites, homework, etc.). The material is usually badly referenced on Google, but can be pretty good depending on what you find.

I'm incredibly impressed. Keep up the great work, but most importantly, hold on to your passion and care!

All the best,

-HG

/e: this was also a trip down memory lane to my time at Uni and why I fell in love with compsci. It's so inherently beautiful and clever, every teeny tiny bit of it.

I also had a great book when starting out: "Einführung in die Informatik" from Gumm/Sommer (my professors), written in German. They explain round about everything on a basic level in round about 900 pages. Think about how far we've come in the last 15 years, wow! I feel very sentimental now haha

A tip from somebody who is not 17: it's good to have many different research postures. Staying in one of them for too long will give you trouble later on. Took me way too long to figure this out.

I also saw this dynamic in the cryptopals challenges, where I thought the hardest problems were "look up this off-the-shelf cryptosystem and implement it", not "find a flaw in that system you reimplemented with only a few hints.[2]

Like others, I recommend nand2tetris as having answered a lot of the questions I had. It has you implement the hardware of a computer that can execute the program loaded in its memory, from the logic gates and flip-flops up. Then, you implement a compiler that can translate high-level Java-like code into binary. (First to a virtual machine, then assembly, then binary.)

Of course, even then it leaves caps: it's a deliberately toy system, it can't handle programs longer than its memory, the machine does only one-shot programs (and thus can't handle a programmer creating a program live and having it be executed). But it answered a lot of my questions, like how to make memory work, and how function call/return work.

[1] http://understandingbitcoin.us.

[2] Previous comment about it: https://news.ycombinator.com/item?id=36398627

Before Web 3.7+ us self-taught hackers often had to learn out of books, in the dark ages these were basically compilations of actual printed paper and not even a single TikTok video in sight.

No likes or subscribes to the authors either, you had to go to a place that freely stored all these books and find the authors using a catalog of paper index cards. Check this one out sometime:

https://www.amazon.com/But-How-Know-Principles-Computers/dp/...

Exceptionally well done though, keep up the great work.

What a brilliant job you’re doing here. Keep it up and you’ll have a wonderful career.

https://www.flipcode.com/tpractice/

(If you check it out, I’d love to know your opinions).

Also, I wonder what are your local state laws about hiring a 17-year-old to work on open source stuff as an intern. I checked out your github and think you might enjoy part-time discovering what we build. Here is the codebase: https://github.com/Qbix/Platform

Appreciate you injecting your own style into the writing. After a decade in the industry I'm sick of soulless reference materials.

As a side note, once OpenAI slurps up your work, the next ChatGPT might not have to lie so much.

> Apparently everything online about how operating systems and CPUs work is terrible

Then it is time to head for the books. Most of the stuff in the web is not organized and coherent. In particular, the "basics" (whether is CPUs, machine learning, etc) are seldom explained.

be warned, here,there be dragons!

I was a little confused about how you only talked about the sources on the internet are kinda poor. But I didn't see any comments about books for research...

Did you use any? Can you recommend some on this topic?

1. <https://manybutfinite.com/category/internals>

I've been doing that for 26 years.

...but I think they'll eventually hit a ceiling.

I wonder if it'll happen soon.

17 to 21-ish is probably my least gluey era of programming. I wrote an MVC framework from scratch, built my own interpreter, my own compiler, accidentally tried to reinvent machine learning and NLP from scratch, all sorts of cool and wonderful things.

Then I discovered money and prior art. Wow you can build things so much faster if you let others tell you “here, just use this”! And frameworks!! Omg jquery makes life so much easier this is amazing.

Many years later now, the stuff that used to count as “just gluing things together” is now considered “super low level advanced stuff”. We’ve built new abstractions on top of those abstractions.

The stuff beginners “can get away with” now, that’s the next generation’s super low level here be dragons stuff. Programming is great that way.

Far more likely someone with an academic approach to programming would be completely overwhelmed when a task requires them to get a base understanding of a bunch of different technologies before moving on.

If you work at a huge company and have a bunch of project managers and designers narrowing specifications down so you can focus entirely on execution sure, but that is rarely the case for most people.

That was me 10 years ago as 30 year old dev just breaking in. Some things never change.

https://mitpress.mit.edu/9780262539807/the-elements-of-compu...

https://www.nand2tetris.org/

It does a fantastic job taking you from nand gates all the way to function calls but in a delightfully interactive way. Instead of just imagining how it all must work in ur head as u read, u get to build it.

I went so far as to build a little simd/gpu that drives an led matrix with my own cpu assembly and programmable shader language.

I bought it 15 years ago and my eyes glossed over the CPU arch section, but maybe I am ready now. I bought 2e recently.

That's a nice little detail, I haven't seen that before

That's not fixing the problem: that's ignoring it. Which might be the right decision if you need the computer to work now, but fixing it would mean it never happens again.

To be clear, that's the bizarre/absurdist arbitrary line I'm tracing to Linkin Park

Thank you for the nitpick on the 4004! I think I will actually make a minor correction about that.

I know about the Program Counter terminology, and explicitly chose not to use it to be more architecture-independent... but maybe it was a mistake not mentioning it at all, considering it's such absurdly prevalent terminology.

So what helped me most was just experimenting a lot, banging my head against a wall repeatedly. When I got stuck I just had to keep trying. Knowing I could Google problems was really helpful, but I also had to learn how to Google. I was motivated by the amazing feeling of finishing something I built, and also the fun of learning and then applying that knowledge.

It's hard to remember my tiny self so I wish I could give better advice. I most of all wish that I had a mentor figure, someone I could ask for questions or who could show me where to look, or even just be a role model. Getting into open source and talking to people online was amazing, although I didn't start that until I was ~12.

It took me a really long time to get where I am. There are probably more efficient ways to do so other than banging my head against things. But it does work! So just encourage them to keep going, and MOST IMPORTANTLY, FOLLOW THEIR INTERESTS!

If they can create/combine algorithms to solve a problem... that's most of programming.

I'd start with the "robot" problem: have them write a set of steps to complete a simple task, and then have them (or better, someone else) go through the steps precisely (no cheating and assuming they meant something they didn't write!). Then iterate and add/remove steps until the task is actually doable. (Disclaimer: idea cribbed from someone else)

That gets them to grok the "everything needs to be in a program, and a program is only everything that's in it" idea.

The traveling salesman problem (recast in whatever form would be most interesting to the kids) and graph theory problems are also especially visual and explorable.

> I talked to GPT-3.5 and GPT-4 a decent amount while writing this article. While they lied to me a lot and most of the information was useless, they were sometimes very helpful for working through problems. LLM assistance can be net positive if you’re aware of their limitations and are extremely skeptical of everything they say. That said, they’re terrible at writing. Don’t let them write for you.

https://cpu.land/epilogue#acknowledgements

To elaborate, I had perhaps 4-6 "conversations" with various GPTs. They consisted of me asking some question or expressing confusion about something I was having trouble researching in case the LLM could either pick up on my confusion and be helpful, or give me a better source to look through than Google. The latter approach never worked, it always made up bullshit, but the former did once or twice — before the conversation deviated into lies, at least, the models helped me get my thoughts straight.

At their best they felt like talking through a problem with someone smarter than me. At their worst they were a waste of time and actively misleading. They were usually at their worst. I did not use language models as primary sources for anything; where they helped me clarify my thoughts, that simply helped me know what to research normally, and the only other time I used them was to find a file in the Linux kernel that contained some code I was looking for but didn't know verbatim.

Otherwise, the article is entirely originally researched and certainly originally written.

Praise is nice, especially when you're young. Stating your young has to dramatically increase praise to criticism ratio in adult spaces like this. No one would care on reddit but we're all old men here lol so the kids stand out. It can be overdone if the person makes the content about themselves instead of the content, or intentionally starts controversy. But this is fine.

Since she states she won a hackathon she's probably a very gifted and motivated young person who is still surrounded with adults telling her she's great, that doesn't mean they're wrong. And sooner or later the adults begin drastically raising the bar for praising you so it's cool for her to get her last couple years out of it.

Was that how it was used? Back in my forum and chan days when that phrase was common I only saw it used to explicitly try to force women off the internet. It was usually quickly followed up with “tits or gtfo” for instance and I never saw an equivalent push on anyone mentioning they were a man

It always seems like the intent is for internet strangers to pat you on the back and tell you how special/precocious you are.

1. I was a precocious kid, and as much as it might rub people the wrong way, there’s nothing wrong with being proud of yourself for that and bringing attention to it. The downside is that you can (at least some of us) have one hell of a shock once you’re out of the wunderkind age range and you’ve made that a core part of your identity.

2. Different standards are warranted with youth. That was a big reason why I prefaced everything with my age growing up. Programmers are notoriously nitpicky and curmudgeonly, but they do tend to have a special place in their heart for youthful curiosity and enthusiasm, and are more willing to give constructive feedback to someone in that phase than a mature adult who won’t just RTFM. I know I feel that way.

- promotes more civil discussion. Commentors are less mean, less dismissive, and when posting criticism it's usually more constructive

- gets the article more attention/traction than normal as a subset of the audience is impressed by the accomplishment/effort given the backstory

Which both benefit the author, and that's fine. We talk about hooks and marketing all the time here; this is harmless but effective, which IMO is the best kind.

This is a young person who’s new to the community. That’s where communities come from!

Without other comment, this meta thread is pushing the author’s personal statement below the fold. As the grown-ass adults in the room, we can have our judgments, but we should try to make a little space, too.

That said, the tone of my reply to OP would have been different if hadn't known their age. Or more likely I would have thought to myself "so you understand CPUs, cool" and moved on.

I'd wish to get as far away as possible from such an attitude, and thus really enjoy when I see people outside of this "norm" to make themselves known and attract more heterogenous people that can enrich the community.

I have to admit, a fault of mine is that I sometimes do the opposite. When I read stories about someone younger than me achieving stuff, it's easy to look for faults to diminish the accomplishment.

"High school student made X? Pft, I found a small flaw when skimming the story therefore the whole thing is probably bad and I don't have to feel bad about not achieving the same at that age."

Yes, that's the point. They're 17, so my expectations are lower.

I am impressed a 17 year old wrote this website.

This is a young person making strides in a hard field, and quite different from majority of peers at their age, but especially today with short attention spans, and TikTok, gaming, other distractions.

Another point is many high schools tend to coddle their students even for very little accomplishments. I was surprised by the attention one 16 yr old student got for making an interesting yet simple science explainer about the sleep cycle. She won the award in the Breakthrough challenge competition, got a 250K scholarship, and given feedback to the tune that she would cure cancer.

There's also a huge competitive gap between US High schools today on average, than many other countries. It would be great for the US system to challenge HS students again and reward real accomplishment.

The age thing is a bit of a red flag now given that too many parents in this industry try to give their kid an advantage by presenting their work as the work of their child. Seed the internet with all of the amazing accomplishments your kid "achieved" at a young age. I now look on the "I'm NN years old and I..." claims with skepticism, to the point where it's a net negative. It makes the project look worse.

Not in this case. It probably a nice guide. Already know how CPUs work so didn't read it, but it's entirely reasonable that a teen could do the work and assemble the details of how a CPU works.

1. https://pubmed.ncbi.nlm.nih.gov/30762417/

If gender is never mentioned, maleness is assumed all the time, and then male users will not realize the abilities of their female peers.

The "I'm 17" part just felt irrelevant to me in a technical work. I.e. it's either technically correct or it's not. However, I can see a strong argument about why it should be in the title. If you care about meta details of the work, it's certainly different and interesting to be produced by someone so young. I suppose part of this is my own life experience talking, and very likely means I'm projecting. When I was a teenager I hated divulging that to others on the internet because they treated me differently when they found out how old I was.

The HN post title is accurate and describes what they did. It makes a choice to center the writer rather than the guide, which has certain consequences about how readers will approach it, but is perfectly appropriate. Of course, your proposed edit makes the same choice, and is arguably more of a brag than the original.

The article title is cute, which is not what you would want for a dry technical manual but appropriate in this case, where the style is supposed to be fun and entertaining as well as informative.

    I'm Helping My High School Peers Learn About CPUs

That's not any judgment about the content, which as far as I can tell is great.

https://news.ycombinator.com/showhn.html

"Please don't post shallow dismissals, especially of other people's work. A good critical comment teaches us something."

https://news.ycombinator.com/newsguidelines.html