File System Hierarchy

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General Information

Some of the most common top level directories in the Linux file system.

Sources

Directory	Used For
/	Root directory; file system tree starts here
/bin	Executable programs needed to repair system; essential during boot
/boot	All files needed to boot the Linux kernel
/dev	Special/device files; refer to physical device
/etc	“etcetera”; configuration files local to the system
/home	User local home directories
/lib and /lib64	Shared libraries used by programs in /boot,/bin, /sbin
/media and /mnt	Mount points for removable media and temporary file systems respectively
/opt	Add on or optional packages
/proc	Pseudo-filesystem that provides information on running processes and the kernel
/root	Home directory for the root user
/run	Process/user specific info created since last boot
/sbin	Similar to /bin, except for system administration not used by regular users
/srv	Directory to use for data used by services (such as NFS, FTP, HTTP)
/sys	To interface with hardware devices managed by the kernel
/tmp	Temporary files that could be deleted without warning during boot
/usr	Directory containing sub directories with program files, libraries, and documentation. Typically mimics the contents of /. Not required during boot.
/var	Files that can change dynamically (log files, mail, and spool files)

It is common to separate the following directories onto their own mount point/partition:

/ ⇒ isolate the core OS away from the rest of the system.
/boot ⇒ isolate kernel boot images, cannot be LVM.
/home ⇒ in order to isolate user data from the rest of the system.
/tmp ⇒ isolate world writeable /tmp to give more secure mount options.
/var ⇒ isolate other variable data that could grow from affecting the rest of the system. (yum cache, common place for applications to write to)
/var/log ⇒ prevent run away log files from affecting the rest of the system.

Top Level Directories