In the "Misc" tab of NetConf is a panel labeled "Information about other hosts". This is where you can assign a name to machines in a local network.
There should already be some entries.
The IP number 127.0.0.1 is a special address assigned to the loopback device. The name "localhost" is already assigned to it.
A loop-back device is a dummy device needed by the system to communicate with itself. This is a required setting so it shouldn't be removed or altered.
The other entry is the IP address assigned earlier to this machine.