The Linux File System
/bin - Binaries
/bin folder contains the basic set of binaries available to every user. It contains the binaries for basic commands such as
mv, and more.
/boot - Bootloaders
/boot folder contains the files necessary to load the operating system when the computer is turned on.
/dev - Devices
/dev folder contains files that represent devices. In Unix-like systems like Linux, disks and just about everything else are represented as files.
sda is a disk. Originally
sd stood for
SCSI device but became a catch-all for any block storage device. The letter that follows
a in this case, represents the order in which the device was found.
/etc - Etcetera (and so on)
/etc folder contains system-wide (as opposed to user-specific) configuration files.
/home - Home Folders
/home directory contains home directories for users other than
/media - Media
/media folder is where removable disks (e.g. CDs, thumb drives) are automatically mounted.
/mnt - Mount
/media folder is where removable disks (e.g. CDs, thumb drives) are manually mounted, very similar to the
/opt - Optional
/opt folder is intended to hold manually installed 3rd-party software.
/proc - Processes
/proc folder contains pseudo files that contain information about processes and resources. All running processes have a folder under
/root - Root (user) Home
/root folder is the
root user's home directory
/run - Run (temporary) Files
/run directory contains temporary files, all of which actually reside in memory. The contents of this directory are deleted upon reboot (because memory is cleared).
/sbin - System (or Super User) Binaries
/sbin folder contains binaries used for system administration tasks including disk and network management. It contains the binaries for commands such as
/srv - Service (or Server) Data
/srv folder stores service/server data to be accessed by external users, for example via a web server.
/sys - System Temporary Files
/sys folder contains temporary files used by the system, all of which are stored in memory (very similar to the
/run folder). The contents of this directory are deleted upon reboot (because memory is cleared).
/tmp - Temporary Files
/tmp folder contains temporary files. Unlike the
/run folder, files stored in
/tmp are less restricted and may be accessed by other users. Generally speaking, developers should prever to use
/tmp for security.
/usr - Users
/usr folder contains "non essential" apps and files used by users (as opposed to the system).
/var - Variable
/var folder contains files that are expected to grow over time (e.g. logs and caches).
Broader Topics Related to Linux File System
A free and open-source operating system