The NS, or Name Server records of a domain, show 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 simplest way to direct 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, if you wish to change some of these records, you'll be able to do it using their system. Put simply, the NS records of a domain name show 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 want to reach. In this way the website you will see is going to be retrieved from the proper location. The name servers normally have a prefix “ns” or “dns” and each domain has at least two NS records. There is no practical difference between the two prefixes, so what kind a web hosting provider will use depends completely on their preference.