What is DNS?
Domain Name System (or DNS) is an essential component of how the Internet works. This is a first part in a multi-part series on Domain Name System. Its basic job is to turn a domain name, such as "unitedlayer.com", into an Internet Protocol (IP) address like 22.214.171.124 (IPv4) or 2607:f3a0:0:1004:5054:ff:feba:e1c5 (IPv6). Computers, services, or resources use this IP address to identify each other on the internet or on a private network.
Read more | PDF