The Name Servers of a domain name show the DNS servers that manage its DNS records. The IP of the website (A record), the mail server that takes care of 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 hosting provider and for any Internet domain to be using them and to be forwarded to their hosting platform, it should have their name servers, or NS records. If you want to open a website, for instance, and you enter the URL, the Internet browser connects to a DNS server, which keeps the NS records for the domain and the request is then pointed to the DNS servers of the hosting company where the A record of the web site is retrieved, allowing you to see the content from the proper location. Usually a domain address has two name servers that start with NS or DNS as a prefix and the contrast between the two is simply visual.