Secret commands, functions, reserved words and others

Hello folks, I was looking at keywords.txt at \Program Files\Arduino\Lib and I realized there are many Commands, Functions, Reserved words and others never mentioned or present in the Arduinos's documentation. Does anybody know something about that secrets ?

The keywords.txt file defines names that are to mean something to the IDE. That is, it tells the IDE how to color the word. There is NOTHING that makes an entry in the file(s) reserved, secret, magic, or anything other than (uselessly) colorful.

The Arduino is programmed in C++. The Arduino Reference pages do not describe all the C++ functions but there are many other websites that do. I usually refer to http://www.cplusplus.com/reference/

I suspect there are few things less secret than the C++ programming language.

...R