The NS, or Name Server records of a domain name, show which servers manage the Domain Name System (DNS) records for it. Setting the name servers of a particular hosting provider for your domain is the simplest 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), etc, so, in case you wish to change any one of these records, you'll be able to do it through their system. Put simply, the NS records of a domain address point out the DNS servers that are authoritative for it, so when you try to open a web address, the DNS servers are contacted to retrieve the DNS records of the Internet domain you are trying to access. This way the web site you will see is going to be retrieved from the right location. The name servers usually have a prefix “ns” or “dns” and each and every 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 exclusively on their preference.