The last freestanding DOS was DOS 6.22
Since then DOS has been hidden by various versions of windows.
Also, since then, many new options have been added to DOS commands.
But in any case, a batch file is nothing more than a list of DOS commands,
interpreted by Command.com
It is NOT, nor was it ever a programming language.
There are also stand alone, "External" dos commands that can be run by themselves.
XCOPY and Deltree.exe are good examples.
So, learn DOS the way it is today.
Cheers!
Shadow