System::Call manual

Is there some "manual" or hep file for everything we can do with System::Call ?

C:\Program Files\NSIS\Docs\System\

There, I found too few examples. In other scripts, here in the forum and in other places, I´ve seen a great amount of uses, but are not explained.
Is System::cal a bridge to Windows built-in commands, making it so misterious?

Did you read my tutorial? Is on signature of plugins or in my wiki.

Thank you!