4.5.2 The filesystem concept in Debian
Following the Unix tradition, the Debian system provides the filesystem under
which physical data on harddisks and other storage devices, and the interaction
with the hardware devices such as console screens and remote serial consoles
are represented in an unified manner.
Each file, directory, named pipe, or physical device on a Debian system has a
data structure called an inode which describes its associated
attributes such as the user who owns it (owner), the group that it belongs to,
the time last accessed, etc. See
/usr/include/linux/fs.h for the exact
definition of struct inode in the Debian GNU/Linux system.
This unified representation of physical entities is very powerful since this
allows us to use the same command for the same kind of operation on many
totally different devices.
All your files could be on one disk --- or you could have 20 disks, some of
them connected to a different computer elsewhere on the network. You can't
tell just by looking at the directory tree, and nearly all commands work just
the same way no matter what physical device(s) your files are really on.