Linux filesystem hierarchy (directory)

To comply with the FSSTND the following directories, or symbolic links to directories, are required in /.       /bin       Essential command binaries
/boot      Static files of the boot loader
 /dev       Device files
 /etc       Host-specific system configuration
  /lib       Essential shared libraries and kernel modules
 /media     Mount point for removeable media
 /mnt       Mount point for mounting a filesystem temporarily
 /opt       Add-on application software packages
 /sbin      Essential system binaries
/srv       Data for services provided by this system
/tmp       Temporary files
/usr       Secondary hierarchy
 /var       Variable data

The following directories, or symbolic links to directories, must be in/, if the corresponding subsystem is installed:

 / -- the root directory     /home User home directories (optional)
/lib<qual> Alternate format essential shared libraries                      (optional)
 /root Home directory for the root user (optional)