By the early 1980s, maintaining a single, centralized host table had become slow and unwieldy and the emerging network required an automated naming system to address technical and personnel issues.
For example, the domain name to the addresses 18.104.22.168 (IPv4) and 260:6d:26bf:1497:aa7 (IPv6).Unlike a phone book, DNS can be quickly updated, allowing a service's location on the network to change without affecting the end users, who continue to use the same host name.This process of using the DNS to assign proximal servers to users is key to providing faster and more reliable responses on the Internet and is widely used by most major Internet services.Each subdomain is a zone of administrative autonomy delegated to a manager.It defines the DNS protocol, a detailed specification of the data structures and data communication exchanges used in the DNS, as part of the Internet Protocol Suite.
Historically, other directory services preceding DNS were not scalable to large or global directories as they were originally based on text files, prominently the hosts file.
Using a simpler, more memorable name in place of a host's numerical address dates back to the ARPANET era.
The Stanford Research Institute (now SRI International) maintained a text file named HOSTS.
Users take advantage of this when they use meaningful Uniform Resource Locators (URLs), and e-mail addresses without having to know how the computer actually locates the services.
An important and ubiquitous function of DNS is its central role in distributed Internet services such as cloud services and content delivery networks.
The Domain Name System delegates the responsibility of assigning domain names and mapping those names to Internet resources by designating authoritative name servers for each domain.