What is DNS?

DNS stands for "Domain Name System". It's a naming system used for computers, services, or any resource pertaining to the internet that uses IP addresses. Its basic function is associating a domain name to an IP address. An often used analogy to explain the Domain Name System is that is serves as the "phone book" for the internet by translating human-friendly computer hostnames into IP addresses. We use this system mainly because internet domain names are easier to remember than IP addresses.

The Domain Name System distributes the responsibility of assigning domain names and mapping those names to IP addresses by designating authoritative name server for each domain. Authoritative name servers are assigned to be responsible for their particular domains, and in turn can assign other authoritative name servers for their sub-domains. This mechanism has made the DNS distributed, fault tolerant, and helped avoid the need for a single central register to be continually consulted and updated.

In general, the Domain Name System also stores other types of information, such as the list of mail servers that accept email for a given domain. By providing a world-wide, distributed keyword-based redirection service, the Domain Name System is an essential component of the functionality of the internet.