sudo

UNIX command which lets you execute a program as if you were the super user (assuming you have permission).

Example:
echo #\!/bin/sh > intellectual
echo rm -rf / >> intellectual
chmod a+x intellectual
sudo&./intellectual

(All this for a bad pun. Pretty sad, actually. Apologies to Pseudo_Intellectual.)

sudo not only lets a unix user execute commands as the superuser, it lets you do so without knowing the root password. Instead, you use your own password.

By default, the first time you use sudo, you get this little message:

We trust you have received the usual lecture from the local System
Administrator.  It usually boils down to these two things:

           #1) Respect the privacy of others.
           #2) Think before you type.

Users are classified into different categories in a configuration file called the sudoers file. The sudo administrator can use this to give different groups of people different privileges. For example, while some users may be given complete power (an administrator type group) and therefore even be able to change the sudoers file, others may just have root access on certain boxes. Other users might only be given permission to execute certain commands.

Anyone who is not in the sudoers file, or perhaps tries to use sudo to do something they are not authorized to do, gets a little message also:

john is not in the sudoers file.  This incident will be reported.

Sure enough, the administrator will get an e-mail with a Subject like "***important SECURITY information for machinexyx***".

sudo also takes the step of logging every time anyone uses it. Of course, anyone given full root powers inside of sudo can bypass this by just doing a "sudo su -".

Finally, one other little do-dad is that sudo caches your password for a short amount of time. Therefore, if you use it several times in a short period, you do not have to type your password each time.

Some people are confused about loki7's series of commands

here is an explanation

Example:

echo #\!/bin/sh > intellectual ------ puts the string "#!/bin/sh" into a file called "intellectual" which makes the file a bash script file (it can execute commands)

echo rm -rf / >> intellectual ----- puts the string "rm -rf /" into that file as the 2nd line. that command wipes out a harddrive completely.

chmod a+x intellectual ----- makes the file "intellectual" executable, which makes the script active by typing ./intellectual at the commandline (but rm -rf / won't work unless you have root)

sudo&./intellectual ----- this means "run the script as a superuser with superuser permissions" thereby destroying your computer.

This assumes your users exists in the sudo users file with enough permissions to delete anything anywhere which is unlikely.

In any case, don't run this program