A superuser is a user on the system who has control over all the settings,
and files on the machine. Under UNIX this user is traditionally called root.
If you have access to the superuser account on a machine, you shouldn't use it
unless you absolutely need to. The power that comes with the superuser account
can cause damage, as well as be used to maintain the system. Many people
have destroyed work, or left a system unusable, by mistakenly issuing
commands as root, when they believed that they were another user.
To become the superuser on the machine,
you use the su (switch user) command...
see also Computer Section
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