CD /D changes the current directory and current drive at the same time. As an example, assume that my current drive is D: and my current directory on C: is the root directory. If I type "cd /d c:\downloads" my current drive will become C: and the current directory on C: will become c:\downloads.
MD can now create multiple levels of directory in a single command. Assume I have no directory called C:\jim. If I type "md c:\jim\fred". NT will create a directory called \jim and then create a subdirectory under \jim called fred.
RD /S does a complete tree delete. "rd /s \jim" will remove directory \jim, even if there are sub-directories and/or files in \jim.
DEL /S can delete in sub-directories. For example, "del /s *.txt" will delete all text files in either the current directory or any sub-directory of the current directory.
FOR /D - Makes wildcards match directory names instead of filenames.
FOR /R - Walks the directory recursively , executing the FOR command in each directory of the tree.
FOR /L - Equivalent to a BASIC FOR/NEXT loop.
In addition, access to FOR variable references has been enhanced. If you write batch files, run HELP FOR from the command line to see all the new features of this command. To see the complete list of commands that have been enhanced in NT 4.0, enter CMD /? on a command line.