It is also possible for a server to have an IP address but not a name. Users who have the IP address can access these servers like any other Web server, but because no name is associated with them, the DNS database does not include them.

In many respects, this is like a private phone number that is not in a public phone listing, and it can be a useful tool to prevent unwanted visitors to a website while it is still under development or if the content is not geared toward the general public.