The Name Servers of a domain name show the DNS servers that are responsible for its DNS records. The IP address of the website (A record), the mail server that manages the emails for a domain name (MX records), any text record in free form (TXT record), directing (CNAME record) etc are taken from the DNS servers of the website hosting provider and for any domain name to be using them and to be directed to their hosting platform, it has to have their name servers, or NS records. If you wish to open an Internet site, for instance, and you type in the URL, the Internet browser connects to a DNS server, which keeps the NS records for the domain and the request is then redirected to the DNS servers of the webhosting provider where the A record of the site is retrieved, so that you can see the content from the right location. Usually a domain name has two name servers that start with NS or DNS as a prefix and the contrast between the two is only visual.