Linux as a multi-user operating system has ONLY one super user, the 'root' account. 

Besides security concerns , access to the system using this user is required in order to perform administrative tasks like system maintenance.

A normal user can also has temporary 'root' permissions by using the 'sudo' command along with their own password (not the root password), but only if they are a member of a specific user group called 'wheel' .

How to add a user 'linuman' to the 'wheel' group

1. Login as root

2. Run the following command:

# usermod -a -G wheel linuxman