The Name Servers of a domain name point out the DNS servers that are responsible for its DNS records. The IP of the site (A record), the mail server that manages the e-mails for a domain name (MX records), any text record in free form (TXT record), forwarding (CNAME record) and so on are taken from the DNS servers of the website hosting company and for any domain address to be using them and to be directed to their hosting platform, it ought to have their name servers, or NS records. If you wish to open an Internet site, for instance, and you input the URL, the Internet browser connects to a DNS server, which keeps the NS records for the domain address and the request is then sent to the DNS servers of the hosting company where the A record of the site is obtained, allowing you to see the content from the right location. Normally a domain name has a couple of name servers that start with NS or DNS as a prefix and the distinction between the two is simply visual.