I've been thinking a lot about documentation and how to get a user up to speed on a code base as quickly and effortlessly (on the part of the user) as possible.<p>I know "best" can be somewhat arbitrary or subjective, but use whichever metric you think is most relevant (organization, clarity, etc...). And, if you'd like, let me know what you think "best" should mean in relation to documentation quality.<p>Also, I know this question has been asked before, but those threads are all several years old, so in that time the documentation pool has obviously changed (and hopefully improved).
<a href="https://freebsd.org/handbook" rel="nofollow">https://freebsd.org/handbook</a><p>It's a comprehensive, yet not too dense, set of documentation for getting people up to speed on how to do things with FreeBSD. You may not find a better one even today.
The reference pages for Mathematica are by far the best docs I've seen for a programming language. They're thorough and each example can be evaluated in place.<p>Online version here [1] is not evaluatable and is rendered to images, but otherwise it's the same content as the desktop version. Specific example [2].<p>[1] <a href="http://reference.wolfram.com/language/" rel="nofollow">http://reference.wolfram.com/language/</a>
[2] <a href="http://reference.wolfram.com/language/ref/Histogram.html" rel="nofollow">http://reference.wolfram.com/language/ref/Histogram.html</a>
I like the official git documentation. There are many tutorials out there but reading through the official doc always makes things clearer to me at least<p><a href="https://git-scm.com/doc" rel="nofollow">https://git-scm.com/doc</a><p>I also like Stripe documentation<p><a href="https://stripe.com/docs" rel="nofollow">https://stripe.com/docs</a>
ZeroMQ Guide has frequently been mentioned on HN as one of the better pieces of software documentation:<p><a href="http://zguide.zeromq.org/" rel="nofollow">http://zguide.zeromq.org/</a><p>It is useful not just for using ZeroMQ, but about learning about distributed systems in general.
<a href="https://www.digifire.in/2016/02/06/interview-with-apoorv-arora-co-founder-at-baatna/" rel="nofollow">https://www.digifire.in/2016/02/06/interview-with-apoorv-aro...</a><p>It's a recently written tech interview for a startup named Baatna. Good read!