Domain Name System

(DNS) The unique name of a collection of computers connected to networks such as the Internet. A general-purpose, replicated, distributed data query service for looking up host IP addresses based on host names. The DNS is hierarchical, consisting of domains, subdomains, sites, and hosts. Unique names are formed from smallest to largest, and are of the form user@host.site.subdomain.domain, where host and site are often optional. On the Internet, domain names typically end with a suffix denoting the type of site:.com (commercial) .edu (educational) .net (network operations) .gov (US government) .mil (US military) .org (organization) .us (United States) .ca (Canada) .uk (United Kingdom) .au (Australia) .cz (Czech Republic) .xx (where xx refers to another country's two-letter abbreviation)