Linux: File system overview

This is a general overview of the Linux directory structure.  There are several variations.
/bin    Common programs, shared by the system, the system administrator and the users.

/boot   The startup files and the kernel, vmlinuz. In recent distributions also grub data. Grub is the GRand Unified Boot loader and is an attempt to get rid of the many different boot-loaders we know today.

/dev    Contains references to all the CPU peripheral hardware, which are represented as files with special properties.

/etc    Most important system configuration files are in /etc, this directory contains data similar to those in the Control Panel in Windows

/home   Home directories of the common users.

/initrd (on some distributions) Information for booting. Do not remove!

/lib    Library files, includes files for all kinds of programs needed by the system and the users.

/lost+found     Every partition has a lost+found in its upper directory. Files that were saved during failures are here.

/misc   For miscellaneous purposes.

/mnt    Standard mount point for external file systems, e.g. a CD-ROM or a digital camera.

/net    Standard mount point for entire remote file systems

/opt    Typically contains extra and third party software.

/proc   A virtual file system containing information about system resources. More information about the meaning of the files in proc is obtained by entering the command man proc in a terminal window. The file proc.txt discusses the virtual file system in detail.

/root   The administrative user’s home directory. Mind the difference between /, the root directory and /root, the home directory of the root user.

/sbin   Programs for use by the system and the system administrator.

/tmp    Temporary space for use by the system.

/usr    Programs, libraries, documentation etc. for all user-related programs.

/var    Storage for all variable files and temporary files created by users, such as log files, the mail queue, the print spooler area, space for temporary storage of files downloaded from the Internet, or to keep an image of a CD before burning it.