We will first set up the resolver. The result from the server is then relayed back to the client. It is a file that controls the resolver and tells it which service to use. Determine the order in which the services are tried. In this case, DNS is used and if it is not available, host table is referenced.
Options are on or off.
Not used by DNS queries. This file tells the resolver which nameserver to use. They are mutually exclusive. If both are used, the one that comes later takes precedence. Specify the IP address of name server to use.