I actually like the su command alot and the more I do with linux the beter I like it...
:-) su is pretty limited - it requires you to know the root password, and although it will run a specified command for you (with su -c) it defaults to giving you a full shell.
sudo is one of the alternatives that is commonly installed these days, and it has a much fuller ACL configuration. Once a user has been authorized to use sudo (via the command visudo, which will (unfortunately for some) make you use the vi editor) then use of sudo will result in a prompt for the user's own password, not root's.
Also, sudo will cache a successful authentication for several minutes, meaning the next time you use it won't need to ask for the password. For extra credit, you can set it up to not bother asking for a password at all, which is probably reasonable only on a machine that cannot be contacted from the Internet.
On a full production system, the ACL from sudo can be used to allow various users to only execute *some* commands as root (or anyone else) - so you can give your backup operators the privs they need to start the backup running, or to restore things - but not to be able to wander around the filesystem looking at anything else ...
-jim
