This screen is used for setting the machine name. The machine name is composed of a hostname and a domain for DNS purposes.

The hostname is the name you want to call this machine. It's one word composed of alphanumerics and dashes. If you enter a fully qualified name (hostname.domain) for the hostname, the domain will be copied to the domain name field.

The domain name is optional, and is the machine domain this computer lives in. If your machine is standalone, or is connected to the internet via a dial-up connection, you may leave this blank without any problems happening. If your machine is attached to a lan, you should have this if you want to properly recieve internet mail on this machine.