RHCSA Rapid Track

The user account types in Linux are the superuser, system users, and regular users.

A user has a primary group and might be a member of supplementary groups.

The /etc/passwd, /etc/group, and /etc/shadow critical files contain user and group information.

You can run commands as the superuser with the su and sudo commands.

The useradd, usermod, and userdel commands manage users.

The groupadd, groupmod, and groupdel commands manage groups.

The passwd command manages passwords for users.

The chage command displays and configures password expiration settings for users.