The Name Servers of a domain show the DNS servers that handle its DNS records. The IP address 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), pointing (CNAME record) and so on are extracted from the DNS servers of the hosting company and for any Internet domain to be using them and to be directed to their hosting platform, it needs to have their name servers, or NS records. If you would like to open a site, for instance, and you type the URL, the web browser connects to a DNS server, which keeps the NS records for the domain name and the request is then forwarded to the DNS servers of the hosting provider where the A record of the site is obtained, so that you can view the content from the right location. Normally a domain name has two name servers that start with NS or DNS as a prefix and the contrast between the two is just visual.