CS50 Lecture by Mark Zuckerberg - 7 December 2005

CS50 · 9.5M views · 2014 · 1:05:35

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Why Hacker News recommends it

HN commenters mine it for early-Facebook history, such as his view on open source, privacy and the problems that shaped its architecture.

What it is

A December 2005 guest lecture by Mark Zuckerberg in Harvard's CS50, discussing Facebook's early days, its technical choices and computer science. It captures him as a 21-year-old founder before Facebook's rise.

Recommended by 2 HN commenters across 2 different months, 2016 to 2025.

What Hacker News said

Recommends syspec · 2022-02 · on “Mark Zuckerberg on the Lex Fridman Podcast [video]”

It's easy to poke fun at Mark because he's mega rich and can come off a little stiff, but he's pretty interesting to listen when he's speaking without a script. Here's Mark when he was 21 giving a lecture at Harvard's CS50: [this video]

Recommends alpine01 · 2025-10 · on “Why is everything so scalable?”

There's a now famous Harvard lecture video on YouTube of Zuckerberg earlier in the Facebook days, where he walks through the issues they hit early on. [this video] I watched it ages ago, but I seem to remember one thing that I liked was that each time they changed the architecture, it was to solve a problem they had, or were beginning to have. They seemed to be staying away from pre-optimization and instead took the approach of tackling problems as they had as they appeared, rather than imagining problems long before/if they occurred. It's a bit like the "perfect is the enemy of done" concept - you could spend 2-3x the time making it much more scalable, but that might have an opportunity cost whi

Cites danso · 2016-01 · on “Angular 2 versus React”

> React is a library. It’s precisely the opposite philosophy of large, comprehensive frameworks like Angular and Ember. So when you select React, you’re free to choose modern best-of-breed libraries that solve your problem best. JavaScript moves fast, and React allows you to swap out small pieces of your application for better libraries instead of waiting around and hoping your framework will innovate. Just an aside, but who would've thought that Facebook would be the one to develop around the Unix philosophy? Yes, I know that Google is a monolith, but it became a monolith over one very specific feature and mission, whereas Facebook had to accompany many kinds of user-interaction and behavio

Cites zangiku · 2017-07 · on “500 Startups admits it kept Australian partner in the dark”

The ones that are good at building something (or at least focused on it) won't be wasting their time trying to "give back" (read: find other opportunities). Zuckerberg did some very minimal "giving back" while building Facebook IIRC (the biggest being an actually useful course he visited at Harvard called CS50, here: [this video] )

Cites danso · 2017-11 · on “Facebook asks users for nude photos in project to combat revenge porn”

I agree, I don't want to sound like a Zuckerberg apologist, but it's simplistic to view the Zuckerberg and Facebook of today as we would a 19-year-old Zuckerberg and his elaborate PHP script. As a trivial example: In 2005, when Facebook was a non-trivial company, Zuckerberg [0] guest lectured at a Harvard CS50 class. When asked if Facebook would contribute to open-source, he said that he didn't foresee it being worth the trouble (can't find the exact timestamp, so this is all IIRC with a grain of salt). Now of course, open-source is a substantial part of Facebook. Is it because Zuckerberg in the following years had a Road to Damascus experience with Richard Stallman? Maybe, but it's more lik

Cites MMS21 · 2021-12 · on “CS50 Lecture by Mark Zuckerberg (7 December 2005)”

[this video] Timestamp of the zucc talking about privacy "We care about it, because if people feel like their information isn't private, then that screws us in the longterm, too."

Cites paulsutter · 2022-07 · on “Beating the Averages (2001)”

But what happens if a company chooses truly the worst language. Like PHP? Oh, right. That was Facebook. They ALSO ran circles around their competitors and crushed them. I hear they are worth /even more/ than Viaweb! Great PHP story: > Dustin was like, 'Hey, I want to help out" > Zuckerberg told Moskovitz, "That's pretty cool. But you don't know any PHP." > "That weekend he went home, bought the book 'PERL for Dummies,' came back, and was like, 'OK, I'm ready to go,'" Zuck said, and told him, "The site's written in PHP, not PERL, dude." - [this video]

Cites simonh · 2022-07 · on “Bill Watterson’s refusal to license Calvin and Hobbes (2016)”

I suspect the difference is that in the past the only way to go commercial was to work with a big corporation. Going to market with something was so hugely expensive, and required extensive marketing and distribution infrastructure, which was all internal to these big concerns. The problem was these companies expected a lot of invasive creative control and long term contracts to give access to those capabilities, which to be fair were hugely expensive to build and operate. Nowadays all of that infrastructure exists as generic services on the internet you can throw together in a few days, with costs that scale with your needs. I recently watched a Q&A Mark Zuckerberg gave to the Harvard CS50