The NS, or Name Server records of a domain name, show which servers deal with the Domain Name System (DNS) records for it. Setting the name servers of a specific host company for your domain is the most effective way to point 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), etc, so, in case you wish to edit some of these records, you will be able to do it using their system. Put simply, the NS records of a domain address point out the DNS servers that are authoritative for it, so when you attempt to open a web address, the DNS servers are contacted to obtain the DNS records of the domain name you are attempting to reach. In this way the website you'll see is going to be retrieved from the proper location. The name servers usually have a prefix “ns” or “dns” and each domain has at least two NS records. There's no functional difference between the two prefixes, so what type a host company is going to use depends completely on their preference.