The domain name system (DNS) stores and associates many types of information with domain names, but most importantly, it translates domain names (computer hostnames) to IP addresses. It also lists mail exchange servers accepting e-mail for each domain. In providing a worldwide keyword-based redirection service, DNS is an essential component of contemporary Internet use.
Useful for several reasons, the DNS pre-eminently makes it possible to attach easy-to-remember domain names (such as "wikipedia.org") to hard-to-remember IP addresses (such as 66.230.200.100). People take advantage of this when they recite URLs and e-mail addresses. In a subsidiary function, the domain name system makes it possible for people to assign authoritative names without needing to communicate with a central registrar each time.
The Domain Name System (abbreviated DNS) is an Internet directory service. DNS is how domain names are translated into IP addresses, and DNS also controls email delivery. If your computer cannot access DNS, your web browser will not be able to find web sites, and you will not be able to receive or send email.
The DNS system consists of three components: DNS data (called resource records), servers (called name servers), and Internet protocols for fetching data from the servers.
The billions of resource records in the DNS are split into millions of files called zones. Zones are kept on authoritative servers distributed all over the Internet, which answer queries based on the resource records stored in the zones they have copies of. Caching servers ask other servers for information and cache any replies. Most name servers are authoritative for some zones and perform a caching function for all other DNS information. Large name servers are often authoritative for tens of thousands of zones, but most name servers are authoritative for just a few zones.
The domain name system (DNS) is the way that Internet domain names are located and translated into Internet Protocol addresses. A domain name is a meaningful and easy-to-remember "handle" for an Internet address.
Because maintaining a central list of domain name/IP address correspondences would be impractical, the lists of domain names and IP addresses are distributed throughout the Internet in a hierarchy of authority. There is probably a DNS server within close geographic proximity to your access provider that maps the domain names in your Internet requests or forwards them to other servers in the Internet.
Short for Domain Name System (or Service or Server), an Internet service that translates domain names into IP addresses. Because domain names are alphabetic, they're easier to remember. The Internet however, is really based on IP addresses. Every time you use a domain name, therefore, a DNS service must translate the name into the corresponding IP address. For example, the domain name www.example.com might translate to 198.105.232.4.
The DNS system is, in fact, its own network. If one DNS server doesn't know how to translate a particular domain name, it asks another one, and so on, until the correct IP address is returned.
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