Filesystem Layout

The Linux Filesystem Hierarchy Standard

Unlike Windows, Linux has one unified directory tree rooted at / (pronounced "slash" or "root"). All disks, partitions, and devices are mounted somewhere under this single tree.

$ ls /
bin  boot  dev  etc  home  lib  lost+found  mnt  opt
proc  root  sbin  tmp  usr  var

Key Directories Explained

/ — Root

The top of the entire filesystem. Every file on the system is under / in some way.

/bin — Essential Binaries

Core command-line programs needed for the system to boot and run in single-user mode: ls, cp, mv, bash, etc.

/boot — Boot Files

Contains the Linux kernel (vmlinuz) and bootloader configuration files (GRUB/LILO).

/dev — Device Files

Special files representing hardware devices. Your first hard disk is /dev/sda, terminals are /dev/tty*.

/etc — Configuration Files

System-wide configuration files. This is where you'll spend a lot of time as an admin. /etc/fstab, /etc/passwd, /etc/hostname all live here.

/home — User Home Directories

Each user has a directory here: /home/alice, /home/bob. Your personal files, settings, and configs live here.

/lib — Shared Libraries

Essential shared libraries needed by binaries in /bin and /sbin.

/mnt — Mount Points

Temporary mount points for attaching extra filesystems (USB drives, network shares, CD-ROMs).

/proc — Process Filesystem

A virtual filesystem exposing kernel and process information in real time. cat /proc/cpuinfo shows your CPU details.

/root — Root's Home

The home directory for the superuser (root), kept separate from /home.

/sbin — System Binaries

Administrative commands used primarily by root: fdisk, ifconfig, reboot.

/tmp — Temporary Files

Temporary files that may be cleared on reboot. Don't store anything important here.

/usr — User Programs

The bulk of your installed software lives under /usr — /usr/bin, /usr/lib, /usr/share, and more.

/var — Variable Data

Files that change frequently: log files (/var/log), mail queues, printer spools, package databases.

Editing Files

To edit configuration files you'll need a text editor. Common choices are:

# nano /etc/hostname
# vi /etc/fstab
# emacs /etc/hosts

For beginners, nano is easiest — on-screen shortcuts are shown at the bottom of the window. Check out our Text Editors guide for more options.