disable/enable root user

hi
im absolutely new to linux and am not quite sure about the "root" concept. how do i know if im "root"? i heard it can be dangerous to be logged in as root user, especially as a newbie, because of accidentally harming the system or making it more accesible to intruders. how can i find out if im logged in as root and log out if i am?
ive done some very basic stuff following guides to install ff3 and oo3 on my aa1. it all worked fine but i read that when installing rpm packages the system would prompt for a password (the one i set up when i started up the first time) but it didnt. oh yeah i activated the advanced mode as well coz i was getting tired of the acer desktop.
so is it possible at all that my system logs in as root when i start up or am i worrying too much?
thx for your replies
alastair

 

Look at this sequence of commands ( on my machine, which is not an Acer-One )
( dx2000 is the hostname, rj is my username ):

Note that the last character of the prompt changes from ' $ ' in ' # '
( 'pwd' = Print Working Directory )
( 'cd' without an argument moves you to your 'home directory' ( symbolised by ' ~ ' ).

On the Acer-One-Linpus you are automatically logged in as a user called 'user'.
With 'sudo' you can do things as root without being asked for a password ( also change root's password ).
But I think that if you try to login via a network, with telnet or ssh you will be asked for the user-password.

Yes and no.

--Japser.