The NS, or Name Server records of a domain name, point out which servers handle the Domain Name System (DNS) records for it. Setting the name servers of a specific host company for your domain is the most convenient way to forward it to their system and all its sub-records are going to be handled on their end. This includes A (the IP address of the server/website), MX (mail server), TXT (free text), SRV (services), CNAME (forwarding), etc, so, in case you want to edit any of these records, you'll be able to do it using their system. In other words, the NS records of a domain name show the DNS servers which are authoritative for it, so when you attempt to open a web address, the DNS servers are contacted to retrieve the DNS records of the domain you want to access. In this way the website you'll see is going to be retrieved from the correct location. The name servers normally have a prefix “ns” or “dns” and each and every domain address has at least 2 NS records. There isn't any functional difference between the two prefixes, so what type a web hosting provider is going to use depends completely on their preference.