I have a new favorite thing. Safari Books Online from O’Reilly Media
Secret: it’s not just books. It is basically Netflix plus Kindle Unlimited for IT training and references. If there is something I want to learn about, instead of searching YouTube and spending time figuring what is good content and what is garbage, Safari has all of O’Reilly’s conference videos as well as all of its own and its partners’ training videos available in the service. And the search interface is excellent.
For instance ‘cgroups’, maybe the topic is covered in a chapter of a book by a different title. Maybe it is a section of a video training series. Maybe there were OSCon talks on the topic. All of it is covered and searchable.
There is great content on YouTube (everything from GoogleTech Talks, and numerous others) but there is a lot of poorly done garbage as well.