Domain Name System

The Domain Name System (usually abbreviated to DNS) is a distributed database which is used on the Internet to hold mappings from human-readable names (such as '.COM') to binary addresses.

The DNS is organized as a hierarchy; like file names in a hierarchical file system, a complete DNS name consists of a number of parts, each one of which selects one of the possibile namespaces (sub-directories) at the next level down. The leaves of the tree usually name individual hosts.

Although the DNS has the capability to hold addresses for a number of different protocol suites, in general it now only hold addresses for the Internet Protocol.