The NS, or Name Server records of a domain name, reveal which servers manage the Domain Name System (DNS) records for it. Setting the name servers of a given host company for your domain address 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), and so forth, so, in case you need to change any one of these records, you'll be able to do it through their system. To put it differently, the NS records of a domain name point out 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 reach. This way the site that you'll see is going to be retrieved from the right location. The name servers typically have a prefix “ns” or “dns” and every single domain name has at least two NS records. There's no practical difference between the two prefixes, so what type a host company is going to use depends entirely on their preference.