A Domain Name Server (DNS) is a critical part of the internet, without which domain names could not be linked to IP addresses. DNS servers are used to resolve human-readable domain names into IP addresses that machines can understand. In other words, DNS servers act as the “phone book” of the internet.
Without DNS servers, we would have to remember the IP address of every website we wanted to visit. This would be a daunting task, especially considering that there are over 4 billion unique IP addresses in use today. Thankfully, DNS servers handle this task for us automatically.
DNS servers are organized into hierarchies, with each level of the hierarchy responsible for a different set of domains. The root DNS servers are at the top of this hierarchy and are responsible for all domains on the internet.