The Linux file system follows the Filesystem Hierarchy Standard (FHS). Key directories include:

• / - Root directory, the top-level directory
• /bin - Essential user binaries (commands)
• /boot - Boot loader files and kernel
• /dev - Device files
• /etc - System configuration files
• /home - User home directories
• /lib - Essential shared libraries
• /media - Mount points for removable media
• /mnt - Temporary mount points
• /opt - Optional software packages
• /proc - Virtual filesystem with process information
• /root - Root user's home directory
• /run - Runtime data
• /sbin - System administration binaries
• /tmp - Temporary files
• /usr - User programs and data
• /var - Variable data (logs, databases, etc.)