The NS, or Name Server records of a domain, show which servers handle 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 point 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), etc, if you wish to modify any one of these records, you are going to be able to do it using their system. To put it differently, the NS records of a domain address show the DNS servers which are authoritative for it, so when you try to open a web address, the DNS servers are contacted to retrieve the DNS records of the Internet domain you want to reach. That 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 every single domain address has at least 2 NS records. There is absolutely no practical difference between the two prefixes, so which one a web hosting provider will use depends only on their preference.