If your computer name is not recognized by Bonjour, the local network name is Macintosh… Jobs revealed the change following announcements on the new Apple … Your computer’s local hostname is displayed beneath the computer’s name at the top of Sharing preferences.
If your Mac has the exact name of another Mac on your local network, a number is added to the local network name. For example, if your computer’s name is My Computer, your local network name is My-Computer.local. Although everyone knows that Apple Computer was named after the namesake fruit, Steve Jobs has never talked about where the name came from — until now (AFAIK). The local network name is your computer’s name with .local added, and any spaces are replaced with hyphens (-). Formerly Apple Computer, the name change reflects the company’s newfound emphasis on consumer electronics.