DOS and the Macintosh have hierarchical filesystems (1.19) much like those in UNIX and other large systems. But there is an important difference.
On many DOS and Macintosh systems, you start right at the "root" of the filesystem tree. In effect, you start with a blank slate, and create subdirectories to organize your files.
A UNIX system comes with an enormous filesystem tree already developed. When you log in, you start somewhere down in that tree, in a directory created for you by the system administrator (who may even be yourself, if you are administering your own system).
This directory, the one place in the filesystem that is your very own, to store your files (especially the shell setup files (2.2) that you use to customize the rest of your environment) is called your home directory.
Home directories were originally stored in a directory called /usr (and still are on some systems), but are now often stored in other directories, perhaps named /u or /home.
To change your
current directory (1.21)
to your home, type cd
with no pathname; the shell will
assume you mean your home directory.
Article
14.11
explains "nicknames" for your home directory and other users' home
directories.
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