DNS stands for Domain Name System. The DNS translates URL text addresses (such as gkg.net) into a numeric Internet address (such as 216.217.56.2).
Every website hosting provider is required to have at least 2 DNS servers, (up to 13 are possible) which direct traffic to the websites they host.
In order for a domain name to work properly, the Registry must know which DNS servers to query. DNS servers MUST be valid and registered with the registry before they can be used as DNS servers.