CS50 Lecture by Mark Zuckerberg - 7 December 2005

Key ideas

Speaking to a Harvard class in 2005, Zuckerberg explains how cheap rented machines, smart generalists and a make-it-first attitude let a small team scale Facebook.

From a machine transcript of the audio. Quotes link to the moment they are said.

1. 1

   Cheap technology changes who can compete

   Zuckerberg says he has not spent much time worrying about what a company like Google might do. He argues that each generation of architecture lets individuals do more with less, so the old need to raise capital before making anything has gone away. His example is renting machines at about $100 a month.

2. 2

   Make things first, clean up later

   Zuckerberg admits that skipping early legal setup left Facebook with annoying problems to fix afterwards, and frames the choice as one of opportunity cost. He says many successful companies began as someone trying to build something interesting rather than trying to form a company. He does not tell students to refuse advice, but he thinks people are often too careful.

3. 3

   Get the structure right, then iterate

   Zuckerberg credits one early decision, a separate database for each school, with keeping the friend-path computation manageable and helping the site survive. He contrasts school with a company, where the work is iterative and a first version need not be right as long as the architecture is close. On photos, he says the team had no upfront brilliance and simply spotted problems quickly and judged its options.

4. 4

   Hire for raw intelligence, not skills

   Zuckerberg says Facebook deliberately avoids hiring for specific skills, reasoning that someone with 15 years in an area will mostly keep doing that. He describes pairing new hires with the strongest engineers, wanting a meritocracy, and letting people try ideas in the code that he reviews before anything goes live. He adds that thinking about complexity and scale also applies to growing a sales force.

5. 5

   Let social design solve hard problems

   Zuckerberg says many of Facebook's fixes are social rather than technical: he attributes the rarity of pornography uploads to people using real names and school email addresses. He limits profile visibility to fellow students and gives field-level controls, saying that users who feel their information is not private would hurt the company in the long term. He also says photo tagging only works when nearly everyone around you is on the site.

In Mark’s words

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