[ Thanks to finid
for this link. ]
“Creating and managing user accounts on a Linux system is just
as easy as on any other operating system. However, users new to
Linux might not know the different account types on a Linux
system.“And that is what this tutorial is all about. Very briefly, with
screen shots to clarify, but detailed enough for a new user to get
the whole picture, it describes the different user account types on
a desktop using the GNOME 3 desktop environment, Ubuntu Desktop and
Ubuntu-based distributions. “