File Structure

The Linux filesystem follows a hierarchical structure starting from the root directory (/).

Filesystem Hierarchy Standard (FHS)

Root Directory (/)

The top-level directory containing all other directories and files.

Important Directories

System Directories:

• /bin - Essential user command binaries (ls, cat, cp, etc.)
• /sbin - System administration commands (reboot, shutdown, etc.)
• /lib - System libraries required by binaries
• /lib64 - 64-bit system libraries
• /etc - System configuration files (passwd, hostname, etc.)
• /sys - System and process information
• /proc - Process and system information

Boot and Kernel:

• /boot - Boot loader files and kernel images
• /root - Root user's home directory

User Data:

• /home - User home directories
• /tmp - Temporary files (cleared on reboot)
• /var - Variable data (logs, caches, mail, etc.)
• /opt - Optional application software

Additional:

• /usr - User programs and data (/usr/bin, /usr/lib, /usr/local)
• /srv - Service-specific data
• /dev - Device files (hardware)
• /mnt - Mount points for filesystems
• /media - Mount points for removable media

Navigating the Filesystem

# Print working directory
pwd

# Change directory
cd /home
cd .. # parent directory
cd ~ # home directory

# List directory contents
ls -la # detailed listing
ls -l /etc # list specific directory

# Tree view
tree /home

Understanding Paths

Absolute Paths start with /:

/home/user/documents/file.txt

Relative Paths are relative to current directory:

documents/file.txt
../other-dir/file.txt

Best Practices

• Store user data in /home
• Configuration files go in /etc
• Application logs go in /var/log
• Temporary files belong in /tmp
• Never delete critical system directories