yes, freelancer... u are right...
i remember last time when i study i also learn that the function of the name server is a list of domain name and it IP address
on the other hand, when we type in
www.andomain.com, 1st thing we will direct to the ISP DNS, match the domain and the IP address, then only redirect us to the correct server...
When we update the DNS in our domain CPanel, it will propagate to all the DNS server around the world..each of the DNS already has our record (domain and hosting server ip)