Domain name service (DNS) is like a telephone-directory service for TCP/IP networks. When a program such as a browser or mail server needs to contact a machine for which it has a hostname, it uses DNS to convert that name to a numeric network address. DNS can also do the reverse: convert a numeric address to a hostname.

It is necessary to have DNS set up before you can serve data to the Internet. Although you can contract for DNS service from an external provider, Fedora Core provides a nameserver that you can easily set up to provide your own DNS capability.