Pretend that you have a file folder called C:\data\word_docs, that you use it constantly, and that you would like to refer to it with a shortcut of W:. Open up a command prompt window and issue the following command:
SUBST w: C:\data\word_docs
SUBST is short for substitute. (DOS commands are case-insensitive, so you could enter it as "subst" as well.) So, now, W:\intro.doc is the same thing as C:\data\word_docs\intro.doc — two different ways to refer to the same file.
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