Below I will present a (small but qualitative ) list of those that I think are some of the best sites/blog that a human being can find on the world wide web.
The main criterion I used to draw up the list was to consider how the websites promote the dissemination of knowledge among people and how, over the course of time, they have helped me both with regards to work and in terms of intellectual self-formation. The order in which they are listed is not to be considered restrictive ( except perhaps for the first two ).
Please feel free to criticize the catalog (as long as the criticisms are rational and constructive) and to expand it in the comments.
1) Stack Exchange Concentrator ( https://stackexchange.com/sites )
2) ArXiv e-Print archive ( https://arxiv.org/ )
3) GitHub ( https://github.com/ )
4) Reddit - the front page of the internet ( https://www.reddit.com/ )
5) LessWrong ( https://www.lesswrong.com/ )
6) Shtetl-Optimized ( https://www.scottaaronson.com/blog/ )
7) Slate Star Codex ( https://slatestarcodex.com/author/admin/ )
8) YouTube ( https://www.youtube.com/?hl=it&gl=IT )
9) TED ( https://www.ted.com/#/ )
10) Standford Encyclopedia of Philosophy ( https://plato.stanford.edu/ )
11) Google Scholar ( https://scholar.google.com/ )
12) SciHub (Banned - no more reacheable on the www from my country)