The NS, or Name Server records of a domain name, reveal which servers deal with the Domain Name System (DNS) records for it. Setting the name servers of a particular host company for your domain address is the most effective way to forward it to their system and all its sub-records are going to 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, if you would like to edit some of these records, you'll be able to do it through their system. Put simply, the NS records of a domain name reveal the DNS servers that 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 are trying to access. That way the web site that you will see will be retrieved from the correct location. The name servers normally have a prefix “ns” or “dns” and each domain name has at least two NS records. There is absolutely no practical difference between the two prefixes, so which one a web hosting provider will use depends entirely on their preference.