The NS, or Name Server records of a domain, reveal which servers manage the Domain Name System (DNS) records for it. Setting the name servers of a particular host company for your domain is the most convenient way to forward 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), and so forth, if you would like to edit some of these records, you will be able to do it via their system. Put simply, the NS records of a domain 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 obtain the DNS records of the Internet domain you want to reach. This way the site you'll 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 functional difference between the two prefixes, so what kind a website hosting provider will use depends exclusively on their preference.