UNIX ---1

/ The root of the overall file system namespace.
/bin A symbolic link to the /usr/bin directory. It is the
directory location for the binary files of standard
system commands.
/dev The primary directory for logical device names. The
contents of this directory are symbolic links that point to
device files in the /devices directory.
/devices The primary directory for physical device names.
/etc The directory that holds host-specific configuration files
and databases for system administration.
Introducing / (root) Subdirectories
/export The default directory for commonly shared file systems,
such as users’ home directories, application software, or
other shared file systems.
/home The default directory or mount point for a user’s home
directory.
/kernel The directory of platform-independent loadable kernel
modules that are required as part of the boot process.
/mnt A convenient, temporary mount point for file systems.
/opt The default directory or mount point for add-on
application packages.
/platform The directory of platform-dependent loadable kernel
modules.
/sbin The single-user bin directory that contains essential
executables that are used during the booting process
and in manual system-failure recovery.
/tmp The directory for temporary files. This directory is
cleared during the boot sequence.
/usr The directory that contains programs, scripts, and
libraries that are used by all system users. The directory
name is an acronym for UNIX® system resources.
/var The directory for varying files, which usually includes
temporary, logging, or status files.

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