In this chapter, you learned:
There are three main types of user account: the superuser, system users, and regular users.
A user must have a primary group and may be a member of one or more supplementary groups.
The three critical files containing user and group information are /etc/passwd, /etc/group, and /etc/shadow.
The su and sudo commands can be used to run commands as the superuser.
The useradd, usermod, and userdel commands can be used to manage users.
The groupadd, groupmod, and groupdel commands can be used to manage groups.
The chage command can be used to configure and view password expiration settings for users.
Click CREATE to build all of the virtual machines needed for the classroom lab environment. This may take several minutes to complete. Once created the environment can then be stopped and restarted to pause your experience.
If you DELETE your lab, you will remove all of the virtual machines in your classroom and lose all of your progress.