Normally, after install the OS (Debian in my case), you don't have sudo access, and you can see this error:

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

To solve it, first log in as root, to do it enter:

su root

Now, as super user, you can run this command:

visudo

With this command we open the sudo configuration file, add at the end this line:

user ALL=(ALL) ALL

Replace 'user' with your user name and save the file.

Don't forget exit from the super user account, simply enter:

exit

Tip:

If you use Debian, and want to change the default text editor for the system, enter this command:

sudo update-alternatives --config editor

A list with all text editor will appear and you can select your favourite.


If you want to know where the sudo incident are reported, xkcd offers you an explanation: