The superuser account, usually called root, comes
preconfigured to facilitate system administration, and should not be used for day-to-day
tasks like sending and receiving mail, general exploration of the system, or
This is because the superuser, unlike normal user accounts, can operate without
limits, and misuse of the superuser account may result in spectacular disasters. User
accounts are unable to destroy the system by mistake, so it is generally best to use
normal user accounts whenever possible, unless you especially need the extra
You should always double and triple-check commands you issue as the superuser, since
an extra space or missing character can mean irreparable data loss.
So, the first thing you should do after reading this chapter is to create an
unprivileged user account for yourself for general usage if you have not already. This
applies equally whether you are running a multi-user or single-user machine. Later in
this chapter, we discuss how to create additional accounts, and how to change between the
normal user and superuser.