Learning about each item separately is tedious; Wikipedia articles can be too general or too detailed and they often miss real life examples. It's a shame because launching one or two commands and seeing the internals in action is the best part of Linux systems! Anyway, this makes the list intimidating for newcomers; it would be great to have an introduction to the internals that cover most of the list.
Pēteris Ņikiforovs to the rescue! He made an excellent article called htop explained . Htop? How is that gonna help? Well, as he says himself: "the best way to learn something is to try to teach it." and this is exactly what he does. He doesn't just present htop and its key-bindings, he teaches about all the metrics to a very fine-grained detail. Each explanation comes with examples and commands (strace!) that you can reproduce on your system. After reading his article, the entire system makes more sense as well as the wikipedia articles.
Thanks for this article Peter, you truly rocks!