file system hierarchy in linux

The first thing if you want to learn about linux is to know the file system hierarchy that exists in linux file system. below is the brief description of directories and its usage in linux

/bin : the bin directory contains several useful commands that are of use to both the system administrator as well as non-privileged user

/boot : for GRUB (GNU Grand Unified Bootloader). This directory contains everything required for the boot process.

/dev : the location of device files. In linux you have to remember that everything is a file or directory

/etc : contains all system related configuration files

/home : user home directories

/initrd : provides the capability to load a RAM disk by the bootloader this RAM disk can then be mounted as the root filesystem and programs can be run from it

/lib : contain kernel modules and those shared library

/lost+found : files that are recovered from crash or unproper shutdown are placed here

/media : this directory contains subdirectory which are used as mount points for removable media such as cdrom and flashdisk

/opt : reserve for all the software add-on packages that are not part of the default installation

/proc : this directory is special because it is also a virtual filesystem, it doesn’t contain real file but runtime system information (system memory, devices mounted, hardware configuration etc). It is also regarded as a control and information center for the kernel

/root : the home directory of the system administrator

/sbin : contain binaries essential for booting, restoring, recovering and/or repairing the system in addition to the binaries in /bin

/usr : contains all the user binaries their documentation, libraries, header files etc. This directory only contain read-only data

/var : contains variable data like system logging files

/srv : contains site-specific data which is served by the system

/tmp : this directory contains mostly files that are required temporarily

source : http://tldp.org/LDP/Linux-Filesystem-Hierarchy