Essential System Directories
/bin → symlink to /usr/bin - Essential user command binaries (ls, cat, cp, etc.)/sbin → symlink to /usr/sbin - Essential system binaries (mount, ifconfig, shutdown, etc.) typically for root/lib → symlink to /usr/lib - Essential shared libraries and kernel modules/lib64 → symlink to /usr/lib64 - 64-bit libraries
Boot and System Configuration
/boot - Boot loader files, kernel images, initramfs/etc - System-wide configuration files
User and Runtime
/home - User home directories/root - Root user's home directory/tmp - Temporary files, cleared on reboot/run - Runtime variable data (PIDs, sockets) since last boot
Virtual/Special Filesystems
/dev - Device files (hard drives, terminals, null, random, etc.)/proc - Virtual filesystem exposing kernel/process information/sys - Virtual filesystem for kernel/hardware information
Optional/Variable Data
/usr - User programs, libraries, documentation (largest directory tree)/var - Variable data (logs, databases, caches, mail spools)/opt - Optional third-party software packages/srv - Data served by the system (web, FTP, etc.)/media - Mount points for removable media (USB, CD-ROM)/mnt - Temporary mount points for filesystems
WSL/System-Specific
- `/lost+found - Filesystem recovery directory (ext4 fsck)
- `/snap - Snap package system files