Usually, when you get a new-to-you console or you boot up an emulator for the first time (try NesterDC, for instance), you can usually find or remember the major games to check out.� But what happens when you need something different to play? This is where the “Hidden Gems” come in.

"How to learn math and physics" - the title is deliberately provocative. Everyone has to learn their own way. I don't know how you should learn math and physics. But presumably you came here looking for advice, so I'll give you some.
My advice is aimed at people who are interested in fundamental theoretical physics and the math that goes along with that. (By "fundamental" physics I mean the search for the basic laws concerning matter and the forces of nature.) If you want to do experiments instead of theory, or other kinds physics like condensed matter physics and astrophysics, or math that has nothing to do with physics, my advice will be of limited use. You should still learn the basics I mention here, but after that you'll have to look elsewhere for suggestions.

Ein kluger Mann hat deshalb einmal gesagt Man muss nicht alles wissen, man muss nur wissen wo es steht. Die folgende Liste enthält die wichtigsten Cheat Sheets Ajax...

It takes years maybe decades to master the commands available to you at the Linux shell prompt. Here are 10 that you will have never heard of or used. They are in no particular order. My favorite is mkfifo.