Root account

The root account has virtually unlimited access to all programs, files, and resources on a system.

The root account is the special user in the /etc/passwd file with the user ID (UID) of 0 and is commonly given the user name, root. It is not the user name that makes the root account so special, but the UID value of 0. This means that any user that has a UID of 0 also has the same privileges as the root user. Also, the root account is always authenticated by means of the local security files.

The root account should always have a password, which should never be shared. The root account should be given a password immediately after the system is installed. Only the system administrator should know the root password. System administrators should only operate as the root user to perform system administration functions that require root privileges. For all other operations, they should return to their normal user account.