Questions about: add-apt-repository

I'm trying to follow the "Installing Cross Toolchain on Ubuntu 10. 04 (Lucid) and 10. 10 (Maverick) Hosts" instructions on wiki
OR you may use the add-apt-repository command. If your release is 'saucy': Depending on your location, you should replace 'us. ' by another country code, referring to a mirror server in your region