Source : Free On-Line Dictionary of Computing

Domain Name System
     
         (DNS) A general-purpose distributed, replicated,
        data query service chiefly used on {Internet} for translating
        {hostnames} into {Internet addresses}.  Also, the style of
        {hostname} used on the Internet, though such a name is
        properly called a {fully qualified domain name}.  DNS can be
        configured to use a sequence of name servers, based on the
        domains in the name being looked for, until a match is found.
     
        The name resolution client (e.g. Unix's gethostbyname()
        library function) can be configured to search for host
        information in the following order: first in the local
        /etc/hosts file, second in {NIS} and third in DNS.  This
        sequencing of Naming Services is sometimes called "name
        service switching".  Under {Solaris} is configured in the file
        /etc/nsswitch.conf.
     
        DNS can be queried interactively using the command {nslookup}.
        It is defined in {STD 13}, {RFC 1034}, {RFC 1035}, {RFC 1591}.
     
        {BIND} is a common DNS server.
     
        {Info from Virtual Office, Inc.
        (http://virtual.office.com/domains.html)}.
     
        (2001-05-14)