Quick Start Guide
For your daily work, you usually log in to your system as normal user. Performing
some administrative tasks or running certain programs such as YaST requires root
permissions. You can easily switch from your normal account to root and back to
your normal user account after accomplishing the administrative task. How to do so
in a shell is described in Section 7.4, “Becoming Root” (page 93). If you are working
with a graphical user interface you are usually prompted to enter the root password
when necessary. Closing the application which required root permissions results in
withdrawal of the root privileges: you automatically switch back to your normal user
account.
While this concept might not look very appealing at rst, it adds to security. A user
without root privileges cannot damage the entire system. Any damage caused is
strictly limited to the user's own account and data. Any operation executed with root
privileges may potentially harm the entire system. Anyone intending to harm a running
Linux system must gain root privileges rst. This is why it is much harder to create
viruses for Linux systems. They must overcome the root barrier rst.
6.1.2 Groups
Every user in a Linux system belongs at least to one group. A group, in this case,
can be dened as a set of connected users with certain collective privileges. Groups
are usually dened according to functional roles or the data and resources the
members of the group need to access. When a new user account is created on your
system, the user is usually assigned to a default, primary group. The system admin-
istrator can change this primary group or assign the user to an additional group, if
necessary.
Figure 6.1 Group Membership for a User in YaST
74 Start-Up