The NS, or Name Server records of a domain name, point out which servers deal with the Domain Name System (DNS) records for it. Setting the name servers of a given hosting provider for your domain is the easiest way to point it to their system and all its sub-records will be managed on their end. This includes A (the IP address of the server/website), MX (mail server), TXT (free text), SRV (services), CNAME (forwarding), and so on, if you would like to change any one of these records, you are going to be able to do it via their system. Put simply, the NS records of a domain address reveal the DNS servers which are authoritative for it, so when you try to open a web address, the DNS servers are contacted to get the DNS records of the Internet domain you are trying to access. In this way the site you'll see will be retrieved from the right location. The name servers usually have a prefix “ns” or “dns” and each domain address has at least 2 NS records. There is absolutely no practical difference between the two prefixes, so which one a host company is going to use depends exclusively on their preference.