7.2 Files Present and Their Locations
Now that you can navigate the directory tree, let’s take a guided tour of the files and
directories you created when you installed Debian. If you’re curious, cd to each
directory and type ls to see its contents. If the listing doesn’t fit on the screen, try
ls | less, where | is the “pipe” character, generally found on the same key with
backslash.
-
/
- As already mentioned, this is the root directory, which contains every other
directory.
-
/root
- But don’t get /confused with /root! /root is the home directory of the
root user, or superuser. It’s a directory called /root, but it isn’t the root
directory /.
-
/home
- This is where all normal users – that is, all users except root – have
their home directories. Each home directory is named after the user
who owns it, for example, /home/jane. If you’re using a large system
at a school or business, your system administrator may create additional
directories to contain home directories: /home1 and /home2 for example.
On some other systems, you’ll see an additional level of subdirectories:
/home/students/username, /home/staff/username, etc.
Your home directory is where you put all your personal work, e-mail and
other documents, and personal configuration preferences. It’s your home
on the system.
-
/bin
- This directory contains “binaries,” executable files that are essential to the
operation of the system. Examples are the shell (bash) and file commands
such as cp.
-
/sbin
- This directory contains “system binaries,” utilities that the root user or
system administrator might want to use, but that you probably won’t
want to use in your day-to-day activities.
-
/usr
- /usr contains most of the files you’ll be interested in. It has many
subdirectories. /usr/bin and /usr/sbin are pretty much like /bin and
/sbin, except that the directories in /usr are not considered “essential to
the operation of the system.”
While not essential to getting the computer working, /usr does contain
the applications you’ll use to get real work done. Also in /usr, you’ll
find the /usr/man, /usr/info, and /usr/doc directories. These contain
manual pages, info pages, and other documentation, respectively. And
don’t forget /usr/games!
-
/usr/local
- The Debian system doesn’t install anything in this directory. You
should use it if you want to install software that you compile yourself
or any software not contained in a Debian package. You can also install
software in your home directory if you’ll be the only one using it.
-
/etc
- /etc contains all the system-wide configuration files. Whenever you want
to change something that affects all users of your computer – such as how
you connect to the Internet or what kind of video card you have – you’ll
probably have to log on as root and change a file in /etc.
-
/tmp
- Here you’ll find temporary files, most of them created by the system.
This directory is generally erased on a regular basis or every time you
reboot the system. You can create files here if you want, just be aware
that they might get deleted automatically.
-
/var
- /var contains “variable” files that the system changes automatically. For
example, incoming mail is stored here. The system keeps a log of its actions
here. There are a number of other automatically generated files here as
well. You’ll mostly be interested in the contents of /var/log, where you
can find error messages that can help you figure out what you’re system’s
up to if something goes wrong.
Clearly there are many more directories on the system – far too many to describe
every one.
For changing things, you’ll usually want to confine yourself to your home
directory and /etc. On a Debian system, there’s rarely an occasion to change
anything else, because everything else is automatically installed for you.
/etc is used to configure the system as a whole. You’ll use your own home
directory, a subdirectory of /home, for configuring your own preferences and
storing your personal data. The idea is that on a day-to-day basis, you confine
yourself to /home/yourname , so there’s no way you can break anything.
Occasionally you log in as root to change something in a system-wide directory, but
only when it’s absolutely necessary. Of course, if you’re using Debian at a
school or business and someone else is the system administrator, you won’t
have root access and will be able to change only your home directory and
any other directory that you own. This limits what you can do with the
system.