[ Thanks to finid
for this link. ]
“User (account) management is one area that received slight
modifications in Ubuntu Desktop 11.10, the latest stable release of
the popular Linux distribution. This short tutorial presents some
information about the guest sessions, what you can do about it -if
you can do anything at all without messing up your system, and how
to set up a standard user account.“Guest Sessions are non-standard accounts that anyone may use
when the data they will generate in the course of using the system
does not have to be persistent. Unlike in Ubuntu 11.04, where, by
default, a guest session can only be started from an active user
session, Ubuntu 11.10 offers access to a guest session from the
login screen and also from an active user session.”