I can not tell why I love the Web so much, maybe it is because I believe openness and sharing are everything.
My first recommendation is youtube.com.
It is a place you can learn anything PERIOD.
But sometimes you get too much noise on youtube, if I want to learn a thing quickly, I always find it more efficient to go right to its Wikipedia page. All content is reviewed by everyone in the world, which makes the content very trustworthy.
So Wikipedia is my second recommendation.
My third recommendation is Github.com.
Youtube and Wikipedia are mostly about sharing knowledge. Github push sharing to a new level by sharing people’s work. If you are going to build a piece of software, there is a good chance that someone has already built something similar on Github.com.
It’s no exaggeration to say that Github changed the way how programmers do software.
For the last 15 years, most of my time was on these 3 sites.