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 name is the most convenient way to forward it to their system and all its sub-records will 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), and so forth, if you want to modify any of these records, you are going to be able to do it by using their system. Put simply, the NS records of a domain point out the DNS servers which are authoritative for it, so when you attempt to open a web address, the DNS servers are contacted to get the DNS records of the domain you are trying to reach. In this way the web site that you're going to see is going to be retrieved from the correct location. The name servers typically have a prefix “ns” or “dns” and each domain name has at least two NS records. There's no sensible difference between the two prefixes, so what type a website hosting provider is going to use depends completely on their preference.