Linux - Linux directory hierarchy structure

Top-Level Structure (Root Directory)

In Linux, everything starts from the root directory, which is simply:

/

From there, you’ll find several important subdirectories. Here’s a breakdown of the most common ones:

1. / – Root

• The top of the filesystem.

• All other directories are placed under this.

• Not to be confused with the root user (which is /root).

2. /bin – Essential Binaries

• Contains basic command-line programs (like ls, cp, rm, mv, etc.).

• These are needed even if no other parts of the system are available.

3. /sbin – System Binaries

• Like /bin, but for system-level tools (used by root or for system repair).

• Includes commands like reboot, fdisk, etc.

4. /etc – Configuration Files

• Stores system-wide configuration files.

• For example: network settings, startup scripts, user accounts.

5. /home – User Home Directories

• Each regular user has a personal folder here:

  • /home/student

  • /home/alex

• This is where your documents, downloads, and personal files go.

6. /root – Root User’s Home Directory

• Not the same as /

• This is the home directory for the root user (administrator).

• Like /home/root, but special.

7. /var – Variable Files

• For data that changes frequently, such as:

  • Logs (/var/log)

  • Mail

  • Print spool files

8. /usr – User Software and Applications

• Contains most of the installed software, documentation, and libraries.

• Think of it like “Program Files” on Windows.

Subfolders:

• /usr/bin: Apps and commands for users

• /usr/sbin: Admin/system tools

• /usr/lib: Program libraries

• /usr/share: Shared data and documentation

9. /lib – Shared Libraries

• Contains essential libraries (like DLLs in Windows) used by /bin and /sbin.

10. /tmp – Temporary Files

• Stores temporary files created by users or applications.

• Automatically cleared on reboot.

11. /dev – Device Files

• Represents hardware devices as files.

• Examples: /dev/sda (hard disk), /dev/usb, etc.

12. /proc – Process Info

• Virtual directory that gives real-time info about running processes.

• Try: cat /proc/cpuinfo or cat /proc/meminfo

13. /boot – Boot Loader Files

• Contains the Linux kernel and files needed to boot the system.

• Includes: vmlinuz, initrd, grub/

14. /mnt and /media – Mount Points

• Temporary mount points for external drives, USBs, CDs:

  • /mnt/usb

  • /media/username/drive_name

15. /opt – Optional Software

• Used to install third-party or optional software not managed by the package manager.

16. /srv – Service Data

• Stores data for services like web servers or FTP servers.

• For example: website files hosted on your system.

Visual diagram

Summary Table