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 specific hosting provider for your domain is the most effective 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), and so forth, so if you would like to edit any of these records, you'll be able to do it by using their system. Put simply, the NS records of a domain name show the DNS servers which are authoritative for it, so when you attempt to open a web address, the DNS servers are contacted to get the DNS records of the domain name you want to access. In this way the web site you'll see is going to be retrieved from the right location. The name servers normally have a prefix “ns” or “dns” and every single domain has at least 2 NS records. There isn't any functional difference between the two prefixes, so what kind a host company will use depends completely on their preference.