The NS, or Name Server records of a domain name, reveal which servers handle 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 forward it to their system and all its sub-records will be taken care of 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 need to edit any of these records, you are going to be able to do it by using their system. To put it differently, the NS records of a domain name reveal 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 Internet domain you are attempting to reach. In this way the website that you'll see is going to be retrieved from the proper location. The name servers typically have a prefix “ns” or “dns” and each domain name has at least 2 NS records. There's no sensible difference between the two prefixes, so what kind a website hosting provider is going to use depends exclusively on their preference.