<programming, operating system> (Or "application", "app") A
	complete, self-contained program that performs a specific
	function directly for the user.  This is in contrast to system
	software such as the {operating system} {kernel}, {server}
	processes and libraries which exists to support application
	programs.

	Editors for various kinds of documents, {spreadsheets}, and
	text formatters are common examples of applications.  Network
	applications include clients such as those for {FTP},
	{electronic mail}, {telnet} and {WWW}.

	The term is used fairly loosely, for instance, some might say
	that a client and server together form a distributed
	application, others might argue that editors and compilers
	were not applications but tools for building applications.

	One distinction between an application program and the
	operating system is that applications always run in "user
	mode" (or "non-privileged mode"), while operating systems and
	related utilities may run in "supervisor mode" (or "privileged
	mode").

	The term may also be used to distinguish programs which
	communicate via a {graphical user interface} from those which
	are executed from the {command line}.

	(1994-11-28)

<messaging> (e-mail) Messages automatically passed from one
	computer user to another, often through computer {networks}
	and/or via {modems} over telephone lines.

	A message, especially one following the common {RFC 822}
	{standard}, begins with several lines of {headers}, followed
	by a blank line, and the body of the message.  Most e-mail
	systems now support the {MIME} {standard} which allows the
	message body to contain "{attachments}" of different kinds
	rather than just one block of plain {ASCII} text.  It is
	conventional for the body to end with a {signature}.

	Headers give the name and {electronic mail address} of the
	sender and recipient(s), the time and date when it was sent
	and a subject.  There are many other headers which may get
	added by different {message handling systems} during delivery.

	The message is "composed" by the sender, usually using a
	special program - a "{Mail User Agent}" (MUA).  It is then
	passed to some kind of "{Message Transfer Agent}" (MTA) - a
	program which is responsible for either delivering the message
	locally or passing it to another MTA, often on another {host}.
	MTAs on different hosts on a network often communicate using
	{SMTP}.  The message is eventually delivered to the
	recipient's {mailbox} - normally a file on his computer - from
	where he can read it using a mail reading program (which may
	or may not be the same {MUA} as used by the sender).

	Contrast {snail-mail}, {paper-net}, {voice-net}.

	The form "email" is also common, but is less suggestive of the
	correct pronunciation and derivation than "e-mail".  The word
	is used as a noun for the concept ("Isn't e-mail great?", "Are
	you on e-mail?"), a collection of (unread) messages ("I spent
	all night reading my e-mail"), and as a verb meaning "to send
	(something in) an e-mail message" ("I'll e-mail you (my
	report)").  The use of "an e-mail" as a count noun for an
	e-mail message, and plural "e-mails", is now (2000) also well
	established despite the fact that "mail" is definitely a mass
	noun.

	Oddly enough, the word "emailed" is actually listed in the
	Oxford English Dictionary.  It means "embossed (with a raised
	pattern) or arranged in a net work".  A use from 1480 is
	given.  The word is derived from French "emmailleure",
	network.  Also, "email" is German for enamel.

	{The story of the first e-mail message
	(http://www.pretext.com/mar98/features/story2.htm)}.

	(2002-07-14)

<messaging> (Plural "fora" or "forums") Any discussion group
	accessible through a dial-in {BBS} (e.g. {GEnie}, {CI$}), a
	{mailing list}, or a {Usenet} {newsgroup} (see {network,
	the}).  A forum functions much like a {bulletin board}; users
	submit {postings} for all to read and discussion ensues.

	Contrast real-time {chat} or point-to-point personal {e-mail}.

	[{Jargon File}]

	(1998-01-18)