Linux is a multiuser operating system—you can work with several different users on the same computer at the same time. In this book, you’ll mainly use the user pi, because it comes with the Raspbian image automatically. This is convenient, but sometimes it’s handy to create different users for different tasks. Also, pi is a very powerful user that has full administrative rights and can change nearly every aspect of the system. You don’t want to grant all privileges to all users. It’s always a good idea to work with only the administrative rights you need to get the job done. That way, you can’t harm the system by accident.
Adding a new user to Linux is easy using the adduser command.
pi@raspberrypi ~ $ sudo adduser maik