<statistics, mathematics> The practice, study or result of the
	application of mathematical {functions} to collections of
	{data} in order to summarise or {extrapolate} that data.

	The subject of statistics can be divided into descriptive
	statistics - describing data, and analytical statistics -
	drawing conclusions from data.

	(1997-07-16)

<programming> One of a sequence of copies of a program, each
	incorporating new modifications.  Each version is usually
	identified by a number, commonly of the form X.Y where X is
	the major version number and Y is the release number.
	Typically an increment in X (with Y reset to zero) signifies a
	substantial increase in the function of the program or a
	partial or total re-implementation, whereas Y increases each
	time the progam is changed in any way and re-released.

	Version numbers are useful so that the user can know if the
	program has changed ({bugs} have been fixed or new functions
	added) since he obtained his copy and the programmer can tell
	if a bug report relates to the current version.  It is thus
	always important to state the version when reporting bugs.
	Statements about compatibility between different software
	components should always say which versions they apply to.

	See {change management}.

	(1997-12-07)

Common term for "computer", usually when considered at the
	hardware level.  The {Turing Machine}, an early example of
	this usage, was however neither hardware nor software, but
	only an idea.

	[Earlier use?]

	(1995-02-15)

<World-Wide Web> A {Java} program which can be distributed as
	an attachment in a {World-Wide Web} document and executed by a
	Java-enabled {web browser} such as Sun's {HotJava},
	{Netscape Navigator} version 2.0, or {Internet Explorer}.

	Navigator severely restricts the applet's file system and
	network access in order to prevent accidental or deliberate
	security violations.  Full Java applications, which run
	outside of the browser, do not have these restrictions.

	Web browsers can also be extended with {plug-ins} though these
	differ from applets in that they usually require manual
	installation and are {platform}-specific.  Various other
	languages can now be embedded within {HTML} documents, the
	most common being {JavaScript}.

	Despite Java's aim to be a "write once, run anywhere"
	language, the difficulty of accomodating the variety of
	browsers in use on the Internet has led many to abandon
	client-side processing in favour of {server}-side Java
	programs for which the term {servlet} was coined.

	Merriam Webster "Collegiate Edition" gives a 1990 definition:
	a short application program especially for performing a simple
	specific task.

	(2002-07-12)

<hardware> A {SCSI} device that executes a command from a
	{SCSI initiator} to perform some task.  Typically the target
	is a SCSI peripheral device but the {host adapter} can also be
	a target.

	(1999-02-10)

<language, compiler> (JDK) A free {Sun Microsystems} product
	which provides the {environment} required for programming in
	{Java}.  The JDK is available for a variety of {platforms},
	but most notably {Sun Solaris} and {Microsoft Windows}.

	{Home (http://java.sun.com/products/jdk/1.1/index.html)}.

	[Version?]

	(1997-09-04)

1. To copy {data} (often {program} {code} to be {run}) into
	{memory}, possibly {parsing} it somehow in the process.
	E.g. "{WordPerfect} can't load this {RTF} file - are you sure
	it didn't get corrupted in the {download}?"  Opposite of
	{save}.

	2. The degree to which a computer, {network}, or other
	resource is used, sometimes expressed as a percentage of the
	maximum available.  E.g. "What kind of CPU load does that
	program give?", "The network's constantly running at 100%
	load".  Sometimes used, by extension, to mean "to increase the
	level of use of a resource".  E.g. "Loading a spreadsheet
	really loads the CPU".  See also: {load balancing}.

	3. To {install} a piece of {software} onto a system.
	E.g. "The computer guy is gonna come load Excel on my laptop
	for me".  This usage is widely considered to be incorrect.

	(2002-07-02)

<electronics> Part of a system output presented at its input.
	Feedback may be unintended.  When used as a design feature,
	the output is usually transformed by passive components which
	attenuate it in some manner; the result is then presented at
	the system input.

	Feedback is positive or negative, depending on the sign with
	which a positive change in the original input reappears after
	transformation.  Negative feedback was invented by Black to
	stabilise {vacuum tube} amplifiers.  The behaviour becomes
	largely a function of the feedback transformation and only
	minimally a function of factors such as transistor gain which
	are imperfectly known.

	Positive feedback can lead to instability; it finds wide
	application in the construction of oscillators.

	Feedback can be used to control a system, as in {feedback
	control}.

	(1996-01-02)

<library, networking> {Berkeley} {Unix} networking {socket}
	library routine to satisfy a connection request from a remote
	{host}.  A specified socket on the local host (which must be
	capable of accepting the connection) is connected to the
	requesting socket on the remote host.  The remote socket's
	socket address is returned.

	{Unix manual pages}: accept(2), connect(2).

	(1994-11-08)

<jargon> 1. A good property or behaviour (as of a program).
	Whether it was intended or not is immaterial.

	2. An intended property or behaviour (as of a program).
	Whether it is good or not is immaterial (but if bad, it is
	also a {misfeature}).

	3. A surprising property or behaviour; in particular, one that
	is purposely inconsistent because it works better that way -
	such an inconsistency is therefore a {feature} and not a
	{bug}.  This kind of feature is sometimes called a {miswart}.

	4. A property or behaviour that is gratuitous or unnecessary,
	though perhaps also impressive or cute.  For example, one
	feature of {Common LISP}'s "format" function is the ability to
	print numbers in two different Roman-numeral formats (see
	{bells, whistles, and gongs}).

	5. A property or behaviour that was put in to help someone
	else but that happens to be in your way.

	6. A bug that has been documented.  To call something a
	feature sometimes means the author of the program did not
	consider the particular case, and that the program responded
	in a way that was unexpected but not strictly incorrect.  A
	standard joke is that a bug can be turned into a {feature}
	simply by documenting it (then theoretically no one can
	complain about it because it's in the manual), or even by
	simply declaring it to be good.  "That's not a bug, that's a
	feature!" is a common catch-phrase.  Apparently there is a
	Volkswagen Beetle in San Francisco whose license plate reads
	"FEATURE".

	See also {feetch feetch}, {creeping featurism}, {wart}, {green
	lightning}.

	The relationship among bugs, features, misfeatures, warts and
	miswarts might be clarified by the following hypothetical
	exchange between two hackers on an airliner:

	A: "This seat doesn't recline."

	B: "That's not a bug, that's a feature.  There is an emergency
	exit door built around the window behind you, and the route
	has to be kept clear."

	A: "Oh.  Then it's a misfeature; they should have increased
	the spacing between rows here."

	B: "Yes.  But if they'd increased spacing in only one section
	it would have been a wart - they would've had to make
	nonstandard-length ceiling panels to fit over the displaced
	seats."

	A: "A miswart, actually.  If they increased spacing throughout
	they'd lose several rows and a chunk out of the profit margin.
	So unequal spacing would actually be the Right Thing."

	B: "Indeed."

	"Undocumented feature" is a common euphemism for a {bug}.

	7. An attribute or function of a {class} in {Eiffel}.

	[{Jargon File}]

	(1995-10-22)

In {object-oriented programming} sending a message to an
	{object} (to invoke a {method}) is equivalent to calling a
	{procedure} in traditional programming languages, except that
	the actual code executed may only be selected at run time
	depending on the {class} of the object.  Thus, in response to
	the message "drawSelf", the method code invoked would be
	different if the target object were a circle or a square.

	(1995-02-16)

<jargon> Different systems (e.g., {programs}, {file formats},
	{protocols}, even {programming languages}) that can work
	together or exchange data are said to be compatible.

	See also {backward compatible}, {forward compatible}.

	(1998-01-15)

<storage> The part of a {disk} which passes under one
	read/write head while the head is stationary.  The number of
	tracks on a disk surface therefore corresponds to the number
	of different radial positions of the head(s).  The collection
	of all tracks on all surfaces at a given radial position is
	known a {cylinder} and each track is divided into {sectors}.

	(1997-07-15)

<software> (Or "option", "flag", "switch", "option switch") An
	argument to a command that modifies its function rather than
	providing data.  Options generally start with "-" in {Unix} or
	"/" in {MS-DOS}.  This is usually followed by a single letter
	or occasionally a digit.

	Some commands require each option to be a separate argument,
	introduced by a new "-" or "/", others allow multiple option
	letters to be concatenated into a single argument with a
	single "-" or "/", e.g. "ls -al".  A few Unix commands
	(e.g. {ar}, {tar}) allow the "-" to be omitted.  Some options
	may or must be followed by a value, e.g. "cc prog.c -o prog",
	sometimes with and sometimes without an intervening space.

	{getopt} and {getopts} are commands for parsing command line
	options.  There is also a {C} library routine called getopt
	for the same purpose.

	(1996-12-11)

1. Executable code, especially a "pure code" portion shared
	between multiple instances of a program running in a
	{multitasking} {operating system}.

	Compare {English}.

	2. Textual material in the mainstream sense; data in ordinary
	{ASCII} or {EBCDIC} representation (see {flat ASCII}).  "Those
	are text files; you can review them using the editor."

	These two contradictory senses confuse hackers too.

	[{Jargon File}]

	(1995-03-16)

<hypertext> A program which allows a person to read
	{hypertext}.  The browser gives some means of viewing the
	contents of {nodes} (or "pages") and of {navigating} from one
	node to another.

	{Netscape Navigator}, {NCSA} {Mosaic}, {Lynx}, and {W3} are
	examples for browsers for the {World-Wide Web}.  They act as
	{clients} to remote {web servers}.

	(1996-05-31)

<operating system> See {Microsoft Windows}, {Windows NT}.

	(1997-11-23)

<jargon> 1. Ready for use.  E.g. "The graph plotter's fixed
	and on-line again".

	2. {Interactive} as opposed to {batch}.  Accessible via a
	computer (or {terminal}), rather than on paper or other
	medium.

	3. Of a user, actively using a computer system, especially the
	{Internet}.  E.g "I haven't been on-line for three days."

	"On-line" should be hyphenated because it is compounded from
	two words but the hyphen is often omitted in names of
	organisations or services.

	(1998-12-22)

1. (Obsolete) The source code for a program, which may be in
	any language, as opposed to the linkable or executable binary
	produced from it by a compiler.  The idea behind the term is
	that to a real hacker, a program written in his favourite
	programming language is at least as readable as English.
	Usage: mostly by old-time hackers, though recognisable in
	context.

	2. The official name of the {database} language used by the
	{Pick} {operating system}, actually a sort of {crufty},
	brain-damaged {SQL} with delusions of grandeur.  The name
	permits {marketroids} to say "Yes, and you can program our
	computers in English!" to ignorant {suits} without quite
	running afoul of the truth-in-advertising laws.

	["Exploring the Pick Operating System", J.E. Sisk et al,
	Hayden 1986].

	[{Jargon File}]

<job> (Or "computer programmer", "developer") Someone who
	writes or debugs {computer programs}, for a living or for fun.
	"Analyst/developer" is a common equivalent job title, implying
	the added role of {system analysis}.  The term may be
	qualified according to the type of software - "{application}
	programmer", "{system programmer}", etc.

	(2000-01-24)

<electronics> The quantity of {charge} per unit time, measured
	in Amperes (Amps, A).  By historical convention, the sign of
	current is positive for currents flowing from positive to
	negative {potential}, but experience indicates that electrons
	are negatively charged and flow in the opposite direction.

	(1995-10-05)

<language> One of the most used {object-oriented} languages, a
	superset of {C} developed primarily by {Bjarne Stroustrup}
	<bs@alice.att.com> at {AT&T} {Bell Laboratories} in 1986.

	In C++ a {class} is a user-defined {type}, syntactically a
	{struct} with {member functions}.  {Constructors} and
	{destructors} are member functions called to create or destroy
	{instances}.  A {friend} is a nonmember function that is
	allowed to access the private portion of a class.  C++ allows
	{implicit type conversion}, {function inlining}, {overloading}
	of operators and function names, and {default function
	arguments}.  It has {streams} for I/O and {references}.

	C++ 2.0 (May 1989) introduced {multiple inheritance},
	{type-safe linkage}, pointers to members, and {abstract
	classes}.

	C++ 2.1 was introduced in ["Annotated C++ Reference Manual",
	B. Stroustrup et al, A-W 1990].

	{MS-DOS
	(ftp://grape.ecs.clarkson.edu/pub/msdos/djgpp/djgpp.zip)},
	{Unix ANSI C++
	(ftp://gnu.org/pub/gnu/g++-1.39.0.tar.Z)} - X3J16
	committee. (They're workin' on it).

	See also {cfront}, {LEDA}, {uC++}.

	{Usenet} newsgroup: {news:comp.lang.c++}.

	["The C++ Programming Language", Bjarne Stroustrup, A-W,
	1986].

	(1996-06-06)

1. A discrepancy between a computed, observed, or measured
	value or condition and the true, specified, or theoretically
	correct value or condition.

	2. <programming> A mental mistake made by a programmer that
	may result in a program {fault}.

	3. (verb) What a program does when it stops as result of a
	programming error.

	(2000-03-28)

1. Not operating.  "The up escalator is down" is considered a
	humorous thing to say, and "The elevator is down" always
	means "The elevator isn't working" and never refers to what
	floor the elevator is on.  With respect to computers, this
	term has passed into the mainstream; the extension to other
	kinds of machine is still hackish.

	2. "go down" To stop functioning; usually said of the
	{system}.  The message from the {console} that every hacker
	hates to hear from the operator is "System going down in 5
	minutes".

	3. "take down", "bring down" To deactivate purposely, usually
	for repair work or {PM}.  "I'm taking the system down to work
	on that bug in the tape drive."  Occasionally one hears the
	word "down" by itself used as a verb in this sense.

	See {crash}; opposite: {up}.

	[{Jargon File}]

	(1994-12-07)

1. <programming> The prototype for an {object} in an
	{object-oriented language}; analogous to a {derived type} in a
	{procedural language}.  A class may also be considered to be a
	set of objects which share a common structure and behaviour.
	The structure of a class is determined by the {class
	variables} which represent the {state} of an object of that
	class and the behaviour is given by a set of {methods}
	associated with the class.

	Classes are related in a {class hierarchy}.  One class may be
	a specialisation (a "{subclass}") of another (one of its
	"{superclasses}") or it may be composed of other classes or it
	may use other classes in a {client-server} relationship.  A
	class may be an {abstract class} or a {concrete class}.

	See also {signature}.

	2. <programming> See {type class}.

	3. <networking> One of three types of {Internet addresses}
	distinguished by their most significant bits.

	3. <language> A language developed by the {Andrew Project}.
	It was one of the first attempts to add {object-oriented}
	features to {C}.

	(1995-05-01)

1. {application program}.

	2. {function application}.

<language, architecture> (JVM) A specification for software
	which interprets {Java} programs that have been compiled into
	{byte-codes}, and usually stored in a ".class" file.  The JVM
	{instruction set} is {stack}-oriented, with variable
	instruction length.  Unlike some other instruction sets, the
	JVM's supports {object-oriented} programming directly by
	including instructions for object {method} invocation (similar
	to {subroutine} call in other instruction sets).

	The JVM itself is written in {C} and so can be {ported} to run
	on most {platforms}.  It needs {thread} support and {I/O} (for
	{dynamic class loading}).  The Java byte-code is independent
	of the platform.

	There are also some hardware implementations of the JVM.

	{Specification
	(http://www.javasoft.com/docs/books/vmspec/html/VMSpecTOC.doc.html)}.

	{Sun's Java chip
	(http://news.com/News/Item/0,4,9328,00.html)}.

	[Documentation?  Versions?]

	(2000-01-03)

<language> (JRE) The part of the {Java Development Kit}
	required to run Java programs.  The JRE consists of the {Java
	Virtual Machine}, the {Java} platform core {classes} and
	supporting files.  It does not include the compiler, debugger
	or other tools present in the JDK.  The JRE is the smallest
	set of executables and files that constitute the standard Java
	platform.

	(1998-11-30)

1. <unit, text> (Sometimes abbreviated "pt") The unit of
	length used in {typography} to specify text character height,
	{rule} width, and other small measurements.

	There are six slightly different definitions: {Truchet point},
	{Didot point}, {ATA point}, {TeX point}, {Postscript point},
	and {IN point}.

	In Europe, the most commonly used is Didot and in the US, the
	formerly standard ATA point has essentially been replaced by
	the PostScript point due to the demise of traditional
	typesetting systems and rise of desktop computer based systems
	running software such as {QuarkXPress}, {Adobe InDesign} and
	{Adobe Pagemaker}.

	There are 20 {twips} in a point and 12 points in a {pica}
	(known as a "Cicero" in the Didot system).

	{Different point systems
	(http://www.vakcer.com/oberon/dtp/fonts/point.htm)}.

	(2004-12-23)

	2. <hardware> To move a {pointing device} so that the
	on-screen pointer is positioned over a certain object on the
	screen such as a {button} in a {graphical user interface}.  In
	most {window systems} it is then necessary to {click} a
	(physical) button on the pointing device to activate or select
	the object.  In some systems, just pointing to an object is
	known as "mouse-over" {event} which may cause some help text
	(called a "tool tip" in {Windows}) to be displayed.

	(2001-05-21)

<programming> To Traverse a data structure, especially an
	{array} or {linked-list} in {core}.

	See also {codewalker}, {silly walk}, {clobber}.

	(2001-04-12)

1. <application, algorithm> To arrange a collection of items
	in some specified order.  The items - {records} in a file or
	data structures in memory - consist of one or more {fields} or
	members.  One of these fields is designated as the "sort key"
	which means the records will be ordered according to the value
	of that field.  Sometimes a sequence of key fields is
	specified such that if all earlier keys are equal then the
	later keys will be compared.  Within each field some ordering
	is imposed, e.g. ascending or descending numerical, {lexical
	ordering}, or date.

	Sorting is the subject of a great deal of study since it is a
	common operation which can consume a lot of computer time.
	There are many well-known sorting {algorithms} with different
	time and space behaviour and programming {complexity}.

	Examples are {quicksort}, {insertion sort}, {bubble sort},
	{heap sort}, and {tree sort}.  These employ many different
	data structures to store sorted data, such as {arrays},
	{linked lists}, and {binary trees}.

	2. <tool> The {Unix} utility program for sorting lines of
	files.

	{Unix manual page}: sort(1).

	(1997-02-12)

<programming> (Or "procedure") A sequence of {instructions}
	for performing a particular task.  Most programming languages,
	including most {machine languages}, allow the programmer to
	define subroutines.  This allows the subroutine code to be
	called from multiple places, even from within itself (in which
	case it is called {recursive}).  The programming language
	implementation takes care of returning control to (just after)
	the calling location, usually with the support of call and
	return instructions at {machine language} level.

	Most languages also allow {arguments} to be passed to the
	subroutine, and one, or occasionally more, {return values} to
	be passed back.

	A {function} is often very similar to a subroutine, the main
	difference being that it is called chiefly for its return
	value, rather than for any {side effects}.

	(1996-10-01)

1. <programming, operating system> A simple item of data that
	identifies a resource.  For example, a {Unix} file handle
	identifies an open file and associated data such as whether it
	was opened for read or write and the current read/write
	position.  On the {Macintosh}, a handle is a pointer to a
	pointer to some dynamically-allocated memory.  The extra level
	of indirection allows on-the-fly {memory compaction} or
	{garbage collection} without invalidating application program
	references to the allocated memory.

	2. <jargon> An alias used intended to conceal a user's true
	identity in an electronic message.  The term is common on
	Citizen's Band and other amateur radio but, in that context
	usually means the user's real name as {FCC} rules forbid
	concealing one's identity.

	Use of grandiose handles is characteristic of {crackers},
	{weenies}, {spods}, and other lower forms of network life;
	true hackers travel on their own reputations.

	Compare {nick}.

	[{Jargon File}]

	(2004-07-20)

<hypertext, World-Wide Web, standard> (HTML) A {hypertext}
	document format used on the {World-Wide Web}.  HTML is built
	on top of {SGML}.  "Tags" are embedded in the text.  A tag
	consists of a "<", a "directive" (in lower case), zero or
	more parameters and a ">".  Matched pairs of directives, like
	"<title>" and "</title>" are used to delimit text which is to
	appear in a special place or style.

	Links to other documents are in the form

	 <a href="http://machine.edu/subdir/file.html">foo</a>

	where "<a>" and "</a>" delimit an "anchor", "href" introduces
	a hypertext reference, which is most often a {Uniform Resource
	Locator} (URL) (the string in double quotes in the example
	above).  The link will be represented in the browser by the
	text "foo" (typically shown underlined and in a different
	colour).

	A certain place within an HTML document can be marked with a
	named anchor, e.g.:

	 <a name="baz">

	The "fragment identifier", "baz", can be used in an href by
	appending "#baz" to the document name.

	Other common tags include <p> for a new paragraph, <b>..</b>
	for bold text, <ul> for an unnumbered list, <pre> for
	preformated text, <h1>, <h2> .. <h6> for headings.

	{HTML} supports some standard {SGML} {national characters} and
	other non-{ASCII} characters through special {escape
	sequences}, e.g. "&eacute;" for a lower case 'e' with an acute
	accent.  You can sometimes get away without the terminating
	semicolon but it's bad style.

	Most systems will ignore the case of tags and attributes but
	lower case should be used for compatibility with {XHTML}.

	The {World-Wide Web Consortium} (W3C) is the international
	{standards} body for HTML.

	Latest version: {XHTML} 1.0, as of 2000-09-10.

	{Home (http://www.w3.org/MarkUp/)}.

	{Character escape sequences
	(http://www.w3.org/hypertext/WWW/MarkUp/ISOlat1.html)}.

	See also {weblint}.

	(2006-01-19)

1. <tool, compression, file format> To create a compressed
	{archive} (a "zip file") from one or more files using
	{PKWare}'s {PKZIP} or a compatible {archiver}.  Its use is
	spreading from {MS-DOS} now that portable implementations of
	the {algorithm} have been written.

	zip is also the name of a {Unix} archiving utility compatible
	with {PKZIP}.  {unzip} is the corresponding de-archiver.

	See also {gzip}, {tar and feather}.

	2. <storage> {Zip Drive}.

	[{Jargon File}]

	(1996-08-26)

<jargon> {Marketroid} jargon for "{software}", "{hardware}",
	"{protocol}" or something else too technical to name.

	The most flagrant abuse of this word has to be "{Windows NT}"
	(New Technology) - {Microsoft}'s attempt to make the
	incorporation of some ancient concepts into their OS sound
	like real progress.  The irony, and even the meaning, of this
	seems to be utterly lost on Microsoft whose {Windows 2000}
	start-up screen proclaims "Based on NT Technology", (meaning
	yet another version of NT, including some {Windows 95}
	features at last).

	See also: {solution}.

	(2001-06-28)

<programming> (API, or "application programming interface")
	The interface (calling conventions) by which an {application
	program} accesses {operating system} and other services.  An
	API is defined at {source code} level and provides a level of
	{abstraction} between the application and the {kernel} (or
	other privileged utilities) to ensure the {portability} of the
	code.

	An API can also provide an interface between a {high level
	language} and lower level utilities and services which were
	written without consideration for the {calling conventions}
	supported by compiled languages.  In this case, the API's main
	task may be the translation of parameter lists from one format
	to another and the interpretation of {call-by-value} and
	{call-by-reference} arguments in one or both directions.

	(1995-02-15)

1. The art of debugging a blank sheet of paper (or, in these
	days of on-line editing, the art of debugging an empty file).

	2. A pastime similar to banging one's head against a wall, but
	with fewer opportunities for reward.

	3. The most fun you can have with your clothes on (although
	clothes are not mandatory).

	[{Jargon File}]

	(2003-02-12)

1. <chat> {Unix}'s simple {talk} command and {protocol}.
	write has been largely superseded by {talk} and then {irc}.

	An enhancement, {RWP}, has been proposed.

	2. <tool> A simple {text editor} for {Windows}.

	(1998-04-28)

<software> Instructions for a computer in some programming
	language, often {machine language}.  The word "code" is often
	used to distinguish instructions from {data} (e.g. "The code
	is marked 'read-only'") whereas "{software}" is used in
	contrast with "{hardware}" and may consist of more than just
	code.

	(2000-04-08)

That which surrounds, and gives meaning to, something else.

	<grammar> In a {grammar} it refers to the symbols before and
	after the symbol under consideration.  If the syntax of a
	symbol is independent of its context, the grammar is said to
	be {context-free}.

Not working properly (of programs).

<programming> A type of {COM} component that can
	self-register, also known as an "ActiveX control".  All COM
	objects implement the "IUnknown" interface but an ActiveX
	control usually also implements some of the standard
	interfaces for embedding, user interface, methods, properties,
	events, and persistence.

	ActiveX controls were originally called "{OLE} Controls", and
	were required to provide all of these interfaces but that
	requirement was dropped, and the name changed, to make ActiveX
	controls lean enough to be downloaded as part of a web page.

	Because ActiveX components can support the OLE embedding
	interfaces, they can be included in web pages.  Because they
	are COM objects, they can be used from languages such as
	{Visual Basic}, {Visual C++}, {Java}, {VBScript}.

	["Understanding ActiveX and OLE", David Chappell, MS Press,
	1996].

	{Home (http://www.microsoft.com/com/tech/activex.asp)}.

	(2002-04-19)

1. <programming> An {address}, from the point of view of a
	programming language.  A pointer may be typed, with its {type}
	indicating the type of data to which it points.

	The terms "pointer" and "reference" are generally
	interchangable although particular programming languages often
	differentiate these two in subtle ways.  For example, {Perl}
	always calls them references, never pointers.  Conversely, in
	C, "pointer" is used, although "a reference" is often used to
	denote the concept that a pointer implements.

	{Anthony Hoare} once said:

	Pointers are like jumps, leading wildly from one part of the
	data structure to another.  Their introduction into high-level
	languages has been a step backward from which we may never
	recover.

	[C.A.R.Hoare "Hints on Programming Language Design", 1973,
	Prentice-Hall collection of essays and papers by Tony Hoare].

	2. <operating system> (Or "mouse pointer") An {icon}, usually
	a small arrow, that moves on the screen in response to
	movement of a {pointing device}, typically a {mouse}.  The
	pointer shows the user which object on the screen will be
	selected etc. when a mouse button is clicked.

	(1999-07-07)

(UK: "sandpit")

	1. <operating system> A protected, limited environment where
	applications (e.g. {Java} programs downloaded from the
	{Internet}) are allowed to "play" without risking damage to
	the rest of the system.

	2. <jargon> A term for the R&D department at many software and
	computer companies (where hackers in commercial environments
	are likely to be found).  The term is half-derisive, but
	reflects the truth that research is a form of creative play.

	Compare {playpen}.

	3. <operating system> {link farm}.

	[{Jargon File}]

	(2001-02-08)

<company> The biggest supplier of {operating systems} and
	other software for {IBM PC} compatibles.  Software products
	include {MS-DOS}, {Microsoft Windows}, {Windows NT},
	{Microsoft Access}, {LAN Manager}, {MS Client}, {SQL Server},
	{Open Data Base Connectivity} (ODBC), {MS Mail}, and {SNA
	Server} for Windows NT.

	Microsoft was founded as "Micro-soft" in 1975 by {Bill Gates}
	(now CEO) and his high school pal Paul Allen.  Their first
	product was a version of {BASIC} for the new {Altair} computer
	[which one?].  In 1980, {IBM} chose Microsoft to supply the
	{operating system} for the {IBM PC}.

	On the UK television program "The Net" in May 1994, {Bill
	Gates} said he was betting his company on the {information
	highway}".

	Quarterly sales $1293M, profits $362M (Aug 1994).

	{Home (http://www.microsoft.com/)}.
	{(ftp://ftp.microsoft.com/)}.

	{Interesting Info and Other Microsoft WWW Servers
	(http://www-drg.microsoft.com/devinfo.htm)}.

	{Microsoft Windows Developer Information
	(http://www-drg.microsoft.com/devinfo.htm)}.

	{Microsoft Research Group Information
	(http://www.research.microsoft.com)}.

	{Win_News
	(http://www.microsoft.com/chicago/ms-www/ms-intro.htm)}.
	maintained by the Personal Operating Systems Division to
	distribute information on {Microsoft Windows}, {MS-DOS} and
	{Windows 95}.

	(1998-11-06)

<operating system> (Or "man page") A part of {Unix}'s
	extensive on-line documentation.  To read a manual page, type

		man [-s<section>] <page>

	at a shell prompt, e.g. "man ftp" (the section number can
	usually be omitted).  Pages are traditionally referred to
	using the notation "page(section)", e.g. ftp(1).

	Under {SunOS} (which is fairly typical), Section 1 covers
	commands, 2 {system calls}, 3 C library routines, 4 devices
	and networks, 5 file formats, 6 games and {demos}, 7
	miscellaneous, 8 system administration.  Each section has an
	introduction which can be obtained with, e.g., "man 2 intro".

	Manual pages are stored as {nroff} source files.  Formatted
	versions are also usually cached.

	{Unix manual page}: man(1).

	{A Linux man gateway (http://www.foldoc.org/man.cgi)}.

	{A Solaris man gateway
	(http://www.medsch.wisc.edu/cgi-bin/pdm/man.pl)}.

	(2000-03-13)

After-sale handholding; something many software vendors
	promise but few deliver.  To hackers, most support people are
	useless - because by the time a hacker calls support he or she
	will usually know the software and the relevant manuals better
	than the support people (sadly, this is *not* a joke or
	exaggeration).  A hacker's idea of "support" is a tte--tte
	or exchange of {electronic mail} with the software's designer.

	[{Jargon File}]

	(1995-02-15)

<World-Wide Web> A complete {free}, {open-source} {web
	browser} from the {Mozilla Foundation} and therefore a true
	code descendent of {Netscape Navigator}.  The first non-{beta
	release} was in late 2004.

	{Firefox Home (http://www.mozilla.org/products/firefox)}.

	(2005-01-26)

<jargon> A {marketroid} term for something he wants to sell
	you without bothering you with the often dizzying distinctions
	between {hardware}, {software}, {services}, {applications},
	{file formats}, companies, brand names and {operating
	systems}.

	"{Flash} is a perfect image-streaming solution."  "What is
	it?"  "Um...  about a thousand dollars."

	See also: {technology}.

	(1998-07-07)

<graphics, World-Wide Web> A {W3C} standard for {vector
	graphics}, based on {XML}.

	{Home (http://www.w3.org/Graphics/SVG/)}.

	(2001-02-06)

<file format> /ping/ (PNG) An extensible {file format} for the
	{lossless}, {portable}, well-compressed storage of {raster
	images}.  PNG provides a patent-free replacement for {GIF} and
	can also replace many common uses of {TIFF}.
	{Indexed-colour}, {greyscale} and {truecolour} images are
	supported, plus an optional {alpha channel}.  Sample depths
	range from 1 to 16 bits.

	PNG is designed for on-line viewing applications, such as the
	{World Wide Web}, so it is fully {streamable} with a
	{progressive display} option.  PNG is robust, providing both
	full file integrity checking and simple detection of common
	transmission errors.  Also, PNG can store {gamma correction}
	and {chromaticity} data for improved colour matching on
	heterogeneous {platforms}.

	{Filename extension}: .png.

	{RFC 2083}.  {W3C PNG pages
	(http://www.w3.org/Graphics/PNG/)}.  {PNG home page
	(http://www.wco.com/~png/)}.

	(1997-08-07)

1. <storage> {DRAM refresh}.

	2. <hardware> {screen refresh}.

	(1998-10-19)

<jargon> (WYSIWYG) /wiz'ee-wig/ Describes a user interface for
	a document preparation system under which changes are
	represented by displaying a more-or-less accurate image of the
	way the document will finally appear, e.g. when printed.  This
	is in contrast to one that uses more-or-less obscure commands
	that do not result in immediate visual feedback.

	True WYSIWYG in environments supporting multiple fonts or
	graphics is rarely-attained; there are variants of this term
	to express real-world manifestations including WYSIAWYG (What
	You See Is *Almost* What You Get) and WYSIMOLWYG (What You See
	Is More or Less What You Get).  All these can be mildly
	derogatory, as they are often used to refer to dumbed-down
	{user-friendly} interfaces targeted at non-programmers; a
	hacker has no fear of obscure commands (compare {WYSIAYG}).
	On the other hand, {Emacs} was one of the very first WYSIWYG
	editors, replacing (actually, at first overlaying) the
	extremely obscure, command-based {TECO}.

	See also {WIMP}.

	(1999-03-03)

<mathematics> {radix}.

<operating system, programming> The process of carrying out
	the {instructions} in a computer program by a computer.

	See also {dry run}.

	(1996-05-13)

<object-oriented> In {object-oriented programming}, an
	instance of the data structure and behaviour defined by the
	object's {class}.  Each object has its own values for the
	{instance variables} of its class and can respond to the
	{methods} defined by its class.

	For example, an object of the "Point" class might have
	instance variables "x" and "y" and might respond to the "plot"
	method by drawing a dot on the screen at those coordinates.

	(2004-01-26)

<theory, programming> (Or "data type") A set of values from
	which a {variable}, {constant}, {function}, or other
	{expression} may take its value.  A type is a classification
	of data that tells the {compiler} or {interpreter} how the
	programmer intends to use it.  For example, the process and
	result of adding two variables differs greatly according to
	whether they are integers, floating point numbers, or strings.

	Types supported by most programming languages include
	{integers} (usually limited to some range so they will fit in
	one {word} of storage), {Booleans}, {floating point numbers},
	and characters.  {Strings} are also common, and are
	represented as {lists} of characters in some languages.

	If s and t are types, then so is s -> t, the type of
	{functions} from s to t; that is, give them a term of type s,
	functions of type s -> t will return a term of type t.

	Some types are {primitive} - built-in to the language, with no
	visible internal structure - e.g. Boolean; others are
	composite - constructed from one or more other types (of
	either kind) - e.g. {lists}, {arrays}, {structures}, {unions}.
	{Object-oriented programming} extends this with {classes}
	which encapsulate both the structure of a type and the
	operations that can be performed on it.

	Some languages provide {strong typing}, others allow {implicit
	type conversion} and/or {explicit type conversion}.

	(2003-12-22)

<programming, tool> A program that converts another program
	from some {source language} (or {programming language}) to
	{machine language} (object code).  Some compilers output
	{assembly language} which is then converted to {machine
	language} by a separate {assembler}.

	A compiler is distinguished from an assembler by the fact that
	each input statement does not, in general, correspond to a
	single machine instruction or fixed sequence of instructions.
	A compiler may support such features as automatic allocation
	of variables, arbitrary arithmetic expressions, control
	structures such as FOR and WHILE loops, variable {scope},
	input/ouput operations, {higher-order functions} and
	{portability} of source code.

	{AUTOCODER}, written in 1952, was possibly the first primitive
	compiler.  {Laning and Zierler}'s compiler, written in
	1953-1954, was possibly the first true working algebraic
	compiler.

	See also {byte-code compiler}, {native compiler}, {optimising
	compiler}.

	(1994-11-07)

<legal> Software may, under various circumstances and in
	various countries, be restricted by patent or {copyright} or
	both.  Most commercial software is sold under some kind of
	{software license}.

	A patent normally covers the design of something with a
	function such as a machine or process.  Copyright restricts
	the right to make and distribute copies of something written
	or recorded, such as a song or a book of recipies.  Software
	has both these aspects - it embodies functional design in the
	{algorithms} and data structures it uses and it could also be
	considered as a recording which can be copied and "performed"
	(run).

	"{Look and feel}" lawsuits attempt to monopolize well-known
	command languages; some have succeeded.  {Copyrights} on
	command languages enforce gratuitous incompatibility, close
	opportunities for competition, and stifle incremental
	improvements.

	{Software patents} are even more dangerous; they make every
	design decision in the development of a program carry a risk
	of a lawsuit, with draconian pretrial seizure.  It is
	difficult and expensive to find out whether the techniques you
	consider using are patented; it is impossible to find out
	whether they will be patented in the future.

	The proper use of {copyright} is to prevent {software piracy}
	- unauthorised duplication of software.  This is completely
	different from copying the idea behind the program in the same
	way that photocopying a book differs from writing another book
	on the same subject.

	{Usenet} newsgroup: {news:misc.legal.computing}.

	["The Software Developer's and Marketer's Legal Companion",
	Gene K. Landy, 1993, AW, 0-201-62276-9].

	(1994-11-16)

1. <language, programming> {programming language}.

	2. <human language> {natural language}.

	(1998-09-07)

1. <mathematics> One instance of some mathematical object
	contained with in another instance, e.g. a {group} which is a
	subgroup.

	2. <theory> ({domain theory}) A {complete partial order} F in
	[X -> Y] is an embedding if

	(1) For all x1, x2 in X, x1 <= x2  <=>  F x1 <= F x2 and

	(2) For all y in Y, {x | F x <= y} is {directed}.

	("<=" is written in {LaTeX} as {\sqsubseteq}).

	(1995-03-27)

1. <operating system, software> The sequence of states of an
	executing {program}.  A process consists of the program {code}
	(which may be shared with other processes which are executing
	the same program), private data, and the state of the
	{processor}, particularly the values in its {registers}.  It
	may have other associated resources such as a {process
	identifier}, open files, {CPU time} limits, {shared memory},
	{child processes}, and {signal handlers}.

	One process may, on some {platforms}, consist of many
	{threads}.  A {multitasking} {operating system} can run
	multiple processes {concurrently} or in {parallel}, and allows
	a process to spawn "child" processes.

	(2001-06-16)

	2. <business> The sequence of activities, people, and systems
	involved in carrying out some business or achieving some
	desired result.  E.g. software development process, project
	management process, configuration management process.

	(2001-06-16)

<character> (Or "ctrl", "^") One (or a pair) of {modifier
	keys} found on all modern {keyboards}.  If the control key is
	held down while pressing and releasing certain other keys then
	a "{control character}" is generated, e.g. holding control and
	hitting "A" generates control-A ({ASCII} code 1).  The ASCII
	code for the control character is generally 64 less than that
	for the unmodified character.

	The control key does not generate any character on its own but
	most modern keyboards and {operating systems} allow a program
	to tell whether each of the individual keys on the keyboard
	(including modifier keys) is pressed at any time.

	Control characters mostly have some kind of "non-printing"
	effect on the output such as ringing the bell (Control-G) or
	advancing to the next line (Control-J).  Most have alternative
	names suggesting these functions (Bell, Line Feed, etc.).

	See {ASCII character table}.

	(1997-07-10)

<language, tool> A {Unix} tool written in {Tcl} and a {script
	language} for automating the operation of {interactive}
	applications such as {telnet}, {FTP}, {passwd}, {fsck},
	{rlogin}, {tip}, etc..  Expect can feed input to other
	programs and perform {pattern matching} on their output.  It
	is also useful for testing these applications.  By adding
	{Tk}, you can also wrap interactive applications in {X11}
	{GUIs}.

	{Home (http://expect.nist.gov/)}.

	["expect: Scripts for Controlling Interactive Tasks", Don
	Libes, Comp Sys 4(2), U Cal Press Journals, Nov 1991].

	(1997-06-09)

<library, networking> {Unix} socket library routine to connect
	a socket that has been created on the local hosts to one at a
	specified socket address on the remote host.

	{Unix manual pages}: connect(2), accept(2).

	(1995-03-21)

1. <storage> Integrated Drive Electronics, see {Advanced
	Technology Attachment}.

	2. <programming, tool> {integrated development environment}.

	3. <company> {Interactive Development Environments}.

	(2002-04-14)

<World-Wide Web> (URL, previously "Universal") A {standard}
	way of specifying the location of an object, typically a {web
	page}, on the {Internet}.  Other types of object are described
	below.  URLs are the form of address used on the {World-Wide
	Web}.  They are used in {HTML} documents to specify the target
	of a {hyperlink} which is often another HTML document
	(possibly stored on another computer).

	Here are some example URLs:

	 http://www.w3.org/default.html
	 http://www.acme.co.uk:8080/images/map.gif
	 http://www.foldoc.org/?Uniform+Resource+Locator
	 http://www.w3.org/default.html#Introduction
	 ftp://wuarchive.wustl.edu/mirrors/msdos/graphics/gifkit.zip
	 ftp://spy:secret@ftp.acme.com/pub/topsecret/weapon.tgz
	 mailto:fred@doc.ic.ac.uk
	 news:alt.hypertext
	 telnet://dra.com

	The part before the first colon specifies the access scheme or
	{protocol}.  Commonly implemented schemes include: {ftp},
	{http} (World-Wide Web), {gopher} or {WAIS}.  The "file"
	scheme should only be used to refer to a file on the same
	host.  Other less commonly used schemes include {news},
	{telnet} or mailto ({e-mail}).

	The part after the colon is interpreted according to the
	access scheme.  In general, two slashes after the colon
	introduce a {hostname} (host:port is also valid, or for {FTP}
	user:passwd@host or user@host).  The {port} number is usually
	omitted and defaults to the standard port for the scheme,
	e.g. port 80 for HTTP.

	For an HTTP or FTP URL the next part is a {pathname} which is
	usually related to the pathname of a file on the server.  The
	file can contain any type of data but only certain types are
	interpreted directly by most {browsers}.  These include {HTML}
	and images in {gif} or {jpeg} format.  The file's type is
	given by a {MIME} type in the HTTP headers returned by the
	server, e.g. "text/html", "image/gif", and is usually also
	indicated by its {filename extension}.  A file whose type is
	not recognised directly by the browser may be passed to an
	external "viewer" {application}, e.g. a sound player.

	The last (optional) part of the URL may be a query string
	preceded by "?" or a "fragment identifier" preceded by "#".
	The later indicates a particular position within the specified
	document.

	Only alphanumerics, reserved characters (:/?#"<>%+) used for
	their reserved purposes and "$", "-", "_", ".", "&", "+" are
	safe and may be transmitted unencoded.  Other characters are
	encoded as a "%" followed by two {hexadecimal} digits.  Space
	may also be encoded as "+".  Standard {SGML} "&<name>;"
	character entity encodings (e.g. "&eacute;") are also accepted
	when URLs are embedded in HTML.  The terminating semicolon may
	be omitted if &<name> is followed by a non-letter character.

	{The authoritative W3C URL specification
	(http://www.w3.org/hypertext/WWW/Addressing/Addressing.html)}.

	(2000-02-17)

<hardware> To press and release a {button} on a {mouse} or
	other {pointing device}.  This generates an {event}, also
	specifying the screen position, which is processed by the
	{window manager} or {application program}.  On a mouse with
	more than one button, the unqualified term usually implies
	pressing the left-most button (with the right index finger),
	other buttons would be qualified, e.g. "{right-click}".
	{Keyboard} modifiers may also be used, e.g. "shift-click",
	meaning to hold down the shift key on the keyboard while
	clicking the mouse button.

	If the mouse moves while the button is pressed then this is a
	{drag}.

	(1995-03-14)

1. A point or vertex in a {graph}.

	2. {network node}.

	3. A {hypertext} document.

<data, database> An area of a {database} {record}, or
	{graphical user interface} {form}, into which a particular
	item of data is entered.

	Example usage: "The telephone number field is not really a
	numerical field", "Why do we need a four-digit field for the
	year?".

	A {database} {column} is the set of all instances of a given
	field from all records in a {table}.

	(1999-04-26)

<language, programming> (Or "source", or rarely "source
	language") The form in which a computer program is written by
	the programmer.  Source code is written in some formal
	programming language which can be compiled automatically into
	{object code} or {machine code} or executed by an
	{interpreter}.

	(1995-01-05)

<operating system> A {utility} program to ease the
	installation of another, probably larger, {application}.  It
	is also possible for {hardware} to have an installer accompany
	it, to install any low level {device drivers} required.

	The installer commonly asks the user to enter desired
	configuration options for the main program or hardware, and
	sets up various initialisation files accordingly, as well as
	copying the main program to a {hard disc}.

	Some badly designed operating systems require applications to
	provide an {uninstaller} because of the number of different
	files modified or created during the installation process.

	(1998-02-09)

<unit> (b) {binary} digit.

	The unit of information; the amount of information obtained by
	asking a yes-or-no question; a computational quantity that can
	take on one of two values, such as false and true or 0 and 1;
	the smallest unit of storage - sufficient to hold one bit.

	A bit is said to be "set" if its value is true or 1, and
	"reset" or "clear" if its value is false or 0.  One speaks of
	setting and clearing bits.  To {toggle} or "invert" a bit is
	to change it, either from 0 to 1 or from 1 to 0.

	The term "bit" first appeared in print in the computer-science
	sense in 1949, and seems to have been coined by the eminent
	statistician, {John Tukey}.  Tukey records that it evolved
	over a lunch table as a handier alternative to "bigit" or
	"binit".

	See also {flag}, {trit}, {mode bit}, {byte}, {word}.

	[{Jargon File}]

	(2002-01-22)