The Name Servers of a domain reveal the DNS servers that deal with its DNS records. The IP of the web site (A record), the mail server that deals with the e-mails for a domain (MX records), any text record in free form (TXT record), directing (CNAME record) and so forth are taken from the DNS servers of the website hosting company and for any Internet domain to be using them and to be pointed to their hosting platform, it should have their name servers, or NS records. If you want to open a website, for instance, and you type the URL, the Internet browser connects to a DNS server, which keeps the NS records for the domain name and the request is then redirected to the DNS servers of the webhosting provider where the A record of the site is obtained, allowing you to see the content from the right location. Ordinarily a domain name has two name servers that start with NS or DNS as a prefix and the distinction between the two is only visual.