The NS, or Name Server records of a domain, show 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 direct 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, if you would like to modify any one of these records, you'll be able to do it via their system. To put it differently, the NS records of a domain address 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 retrieve the DNS records of the domain you want to access. In this way the website you'll see will be retrieved from the proper location. The name servers normally have a prefix “ns” or “dns” and every single domain name has at least two NS records. There is absolutely no practical difference between the two prefixes, so which one a host company is going to use depends solely on their preference.