The NS, or Name Server records of a domain name, show which servers handle the Domain Name System (DNS) records for it. Setting the name servers of a given host company for your domain name 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 on, if you want to edit any of these records, you'll be able to do it by using their system. In other words, the NS records of a domain show the DNS servers which are authoritative for it, so when you try to open a web address, the DNS servers are contacted to obtain the DNS records of the domain you want to access. In this way the web site that you're going to see is going to be retrieved from the right location. The name servers normally have a prefix “ns” or “dns” and each and every domain name has at least two NS records. There is absolutely no practical difference between the two prefixes, so what type a website hosting provider will use depends solely on their preference.