Common Administrative Tasks in Linux
The tasks in this article are common ones that you may need to do when settingup your system and beginning your new life as the system administrator of your own Linux system.
Basic User and Group Concepts
Linux is a truly multiuser operating system. The concept of users and groups in Linux is inherited from the Unix tradition, and among other things provides a very clear and precise distinction between what normal users can do and what a privileged user can do (such as the root user, the superuser and ultimate administrator on a Linux system, who can do anything).
The fact that the system of users and groups and the associated system of permissions is built into the system at the deepest level is one of the reasons why Linux (and Unix in general) is fundamentally secure in a way that Microsoft Windows is not. Although modern versions of Windows have a similar concept of users and groups, the associated concept of the permissions with which a process can be run leaves a lot to be desired.
This is why there are so many Windows vulnerabilities that are based on exploiting the scripting capabilities of programs that are run with user privileges but that turn out to be capable of subverting the system.