/ is traditionally the home directory of the root account on UNIX systems. /root is used on many Linux systems and on some UNIX systems (in order to reduce clutter in the / directory). The root account's home directory may be determined by developer or local preference. Obvious possibilities include /, /root, and /home/root.
If the home directory of the root account is not stored on the root partition it will be necessary to make certain it will default to / if it can not be located.
Note: we recommend against using the root account for mundane things such as mail and news, and that it be used solely for system administration. For this reason, we recommend that subdirectories such as Mail and News not appear in the root account's home directory, and that mail for administration roles such as root, postmaster and webmaster be forwarded to an appropriate user.