<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)

1. <electronics> {push-button}.

	2. <operating system> A graphical representation of an
	electrical {push-button} appearing as part of a {graphical
	user interface}.  Moving the {mouse pointer} over the
	graphical button and pressing one of the physical mouse
	buttons starts some software action such as closing a window
	or deleting a file.

	See also {radio button}.

	(1997-07-07)

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	formerly standard ATA point has essentially been replaced by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)

<hardware, graphics> The most commonly used computer {pointing
	device}, first introduced by {Douglas Engelbart} in 1968.
	The mouse is a device used to manipulate an on-screen
	{pointer} that's normally shaped like an arrow.  With the
	mouse in hand, the computer user can select, move, and change
	items on the screen.

	A conventional {roller-ball mouse} is slid across the surface
	of the desk, often on a {mouse mat}.  As the mouse moves, a
	ball set in a depression on the underside of the mouse rolls
	accordingly.  The ball is also in contact with two small
	shafts set at right angles to each other inside the mouse.
	The rotating ball turns the shafts, and sensors inside the
	mouse measure the shafts' rotation.  The distance and
	direction information from the sensors is then transmitted to
	the computer, usually through a connecting wire - the mouse's
	"tail".  The computer then moves the mouse pointer on the
	screen to follow the movements of the mouse.  This may be done
	directly by the {graphics adaptor}, but where it involves the
	processor the task should be assigned a high {priority} to
	avoid any perceptible delay.

	Some mice are contoured to fit the shape of a person's right
	hand, and some come in left-handed versions.  Other mice are
	symmetrical.

	Included on the mouse are usually two or three buttons that
	the user may press, or click, to initiate various actions such
	as running {programs} or opening {files}.  The left-most
	button (the {primary mouse button}) is operated with the index
	finger to select and activate objects represented on the
	screen.  Different {operating systems} and {graphical user
	interfaces} have different conventions for using the other
	button(s).  Typical operations include calling up a
	{context-sensitive menu}, modifying the selection, or pasting
	text.  With fewer mouse buttons these require combinations of
	mouse and keyboard actions.  Between its left and right
	buttons, a mouse may also have a wheel that can be used for
	scrolling or other special operations defined by the software.
	Some systems allow the mouse button assignments to be swapped
	round for left-handed users.

	Just moving the pointer across the screen with the mouse
	typically does nothing (though some CAD systems respond to
	patterns of mouse movement with no buttons pressed).
	Normally, the pointer is positioned over something on the
	screen (an {icon} or a {menu} item), and the user then clicks
	a mouse button to actually affect the screen display.

	The five most common "gestures" performed with the mouse are:
	{point} (to place the pointer over an on-screen item), {click}
	(to press and release a mouse button), {double-click} {to
	press and release a mouse button twice in rapid succession},
	{right-click} (to press and release the right mouse button},
	and {drag} (to hold down the mouse button while moving the
	mouse).

	Most modern computers include a mouse as standard equipment.
	However, some systems, especially portable {laptop} and
	{notebook} models, may have a {trackball}, {touchpad} or
	{Trackpoint} on or next to the {keyboard}.  These input
	devices work like the mouse, but take less space and don't
	need a desk.

	Many other alternatives to the conventional roller-ball mouse
	exist.  A {tailless mouse}, or {hamster}, transmits its
	information with {infrared} impulses.  A {foot-controlled
	mouse (http://www.footmouse.com/)} is one used on the floor
	underneath the desk.  An {optical mouse} uses a
	{light-emitting diode} and {photocells} instead of a rolling
	ball to track its position.  Some optical designs may require
	a special mouse mat marked with a grid, others, like the
	Microsoft IntelliMouse Explorer, work on nearly any surface.

	{Yahoo!
	(http://dir.yahoo.com/Business_and_Economy/Companies/Computers/Hardware/Peripherals/Input_Devices/Mice/)}.

	{(http://peripherals.about.com/library/weekly/aa041498.htm)}.

	{PC Guide's "Troubleshooting Mice"
	(http://www.pcguide.com/ts/x/comp/mice.htm)}.

	(1999-07-21)

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)

1. <hardware> A visually distinct mark on a display indicating
	where newly typed text will be inserted.  The cursor moves as
	text is typed and, in most modern editors, can be moved around
	within a document by the user to change the insertion point.

	2. <database> In {SQL}, a named control structure used by an
	{application program} to point to a row of data.  The position
	of the {row} is within a {table} or {view}, and the cursor is
	used interactively so select rows from columns.

	(1996-12-27)

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)