Source : Free On-Line Dictionary of Computing

hostname
     
        1. (Or "sitename").  The unique name by which a computer is
        known on a {network}, used to identify it in {electronic
        mail}, {Usenet} {news}, or other forms of electronic
        information interchange.
     
        On {Internet} the hostname is an {ASCII} string,
        e.g. "foldoc.doc.ic.ac.uk" which, consists of a local part
        (foldoc) and a {domain} name (doc.ic.ac.uk).  The hostname is
        translated into an {Internet address} either via the
        /etc/hosts file, {NIS} or by the {Domain Name System} (DNS) or
        {resolver}.  It is possible for one computer to have several
        hostnames (aliases) though one is designated as its
        {canonical} name.
     
        It is often possible to guess a hostname for a particular
        institution.  This is useful if you want to know if they
        operate network services like {anonymous FTP}, {World-Wide
        Web} or {finger}.  First try the institution's name or obvious
        abbreviations thereof, with the appropriate {domain} appended,
        e.g. "mit.edu".  If this fails, prepend "ftp." or "www." as
        appropriate, e.g. "www.data-io.com".  You can use the {ping}
        command as a quick way to test whether a hostname is valid.
     
        The folklore interest of hostnames stems from the creativity
        and humour they often display.  Interpreting a sitename is not
        unlike interpreting a vanity licence plate; one has to
        mentally unpack it, allowing for mono-case and length
        restrictions and the lack of whitespace.  Hacker tradition
        deprecates dull, institutional-sounding names in favour of
        punchy, humorous, and clever coinages (except that it is
        considered appropriate for the official public gateway machine
        of an organisation to bear the organisation's name or
        acronym).  Mythological references, cartoon characters, animal
        names, and allusions to SF or fantasy literature are probably
        the most popular sources for sitenames (in roughly descending
        order).  The obligatory comment is Harris's Lament: "All the
        good ones are taken!"
     
        See also {network address}.
     
        2. {Berkeley} {Unix} command to set and get the application
        level name used by the host.
     
        {Unix manual page}: hostname(1).
     
        (1995-02-16)