The Free On-line Dictionary of Computing (30 December 2018):
1. (Or "sitename"). The unique name by which a computer is
known on a network, used to identify it in electronic
mail, Usenetnews, or other forms of electronic
On the 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 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
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. BerkeleyUnix command to set and get the application
level name used by the host.
Unix manual page: hostname(1).