Mouse (computing)

In computing, a mouse (plural mice or mouses) functions as a pointing
device by detecting two-dimensional motion relative to its supporting

surface. Physically, a mouse consists of a small case, held under one

of the user's hands, with one or more buttons. It sometimes features

other elements, such as "wheels", which allow the user to perform

various system-dependent operations, or extra buttons or features can

add more control or dimensional input. The mouse's motion typically

translates into the motion of a pointer on a display.

The name mouse, coined at the Stanford Research Institute, derives from

the resemblance of early models (which had a cord attached to the rear

part of the device, suggesting the idea of a tail) to the common mouse.

The first marketed integrated mouse — shipped as a part of a computer

and intended for personal computer navigation — came with the Xerox

8010 Star Information System in 1981.

Technologies

Early mice

Douglas Engelbart at the Stanford Research Institute invented the mouse
in 1963 after extensive usability testing. Several other experimental

pointing-devices developed for Engelbart's oN-Line System (NLS)

exploited different body movements — for example, head-mounted devices

attached to the chin or nose — but ultimately the mouse won out because

of its simplicity and convenience. The first mouse, a bulky device

(pictured) used two gear-wheels perpendicular to each other: the

rotation of each wheel translated into motion along one axis. Engelbart

received patent US3541541 on November 17, 1970 for an "X-Y Position

Indicator for a Display System". At the time, Engelbart envisaged that

users would hold the mouse continuously in one hand and type on a

five-key chord keyset with the other.

Mechanical mice

Operating a mechanical mouse.

1: moving the mouse turns the ball.
2: X and Y rollers grip the ball and transfer movement.
3: Optical encoding disks include light holes.
4: Infrared LEDs shine through the disks.
5: Sensors gather light pulses to convert to X and Y velocities.

Bill English, builder of Engelbart's original mouse,[6] invented the

so-called ball mouse in 1972 while working for Xerox PARC.[7] The

ball-mouse replaced the external wheels with a single ball that could

rotate in any direction. It came as part of the hardware package of the

Xerox Alto computer. Perpendicular chopper wheels housed inside the

mouse's body chopped beams of light on the way to light sensors, thus

detecting in their turn the motion of the ball. This variant of the

mouse resembled an inverted trackball and became the predominant form

used with personal computers throughout the 1980s and 1990s. The Xerox

PARC group also settled on the modern technique of using both hands to

type on a full-size keyboard and grabbing the mouse when required.

The ball mouse utilizes two rollers rolling against two sides of the

ball. One roller detects the horizontal motion of the mouse and other

the vertical motion. The motion of these two rollers causes two

disc-like encoder wheels to rotate, interrupting optical beams to

generate electrical signals. The mouse sends these signals to the

computer system by means of connecting wires. The driver software in

the system converts the signals into motion of the mouse pointer along

X and Y axes on the screen.

Ball mice and wheel mice were manufactured for Xerox by Jack Hawley,

doing business as The Mouse House in Berkeley, California, starting in

1975.

Based on another invention by Jack Hawley, proprietor of the Mouse

House, Honeywell produced another type of mechanical mouse.Instead of a

ball, it had two wheels rotating at off axes. Keytronic later produced

a similar product.

Modern computer mice took form at the École polytechnique fédérale de

Lausanne (EPFL) under the inspiration of Professor Jean-Daniel Nicoud

and at the hands of engineer and watchmaker André Guignard.[13] This

new design incorporated a single hard rubber mouseball and three

buttons, and remained a common design until the mainstream adoption of

the scroll-wheel mouse during the 1990s.

Another type of mechanical mouse, the "analog mouse" (now generally

regarded as obsolete), uses potentiometers rather than encoder wheels,

and is typically designed to be plug-compatible with an analog

joystick. The "Color Mouse," originally marketed by Radio Shack for

their Color Computer (but also usable on MS-DOS machines equipped with

analog joystick ports, provided the software accepted joystick input)

was the best-known example.

Optical mice

An optical mouse uses a light-emitting diode and photodiodes to detect

movement relative to the underlying surface, rather than moving some of

its parts — as in a mechanical mouse.

Early optical mice
Early optical mice, circa 1980, came in two different varieties:

Some, such as those invented by Steve Kirsch[15][16] of Mouse Systems
Corporation, used an infrared LED and a four-quadrant infrared sensor

to detect grid lines printed with infrared absorbing ink on a special

metallic surface. Predictive algorithms in the CPU of the mouse

calculated the speed and direction over the grid.
Others, invented by Richard F. Lyon and sold by Xerox, used a 16-pixel

visible-light image sensor with integrated motion detection on the same

chip and tracked the motion of light dots in a dark field of a

printed paper or similar mouse pad.
These two mouse types had very different behaviors, as the Kirsch mouse

used an x-y coordinate system embedded in the pad, and would not work

correctly when the pad was rotated, while the Lyon mouse used the x-y

coordinate system of the mouse body, as mechanical mice do.

The optical sensor from a Microsoft Wireless IntelliMouse Explorer (v.

1.0A).

Modern optical mice

Modern surface-independent optical mice work by using an optoelectronic

sensor to take successive pictures of the surface on which the mouse

operates. As computing power grew cheaper, it became possible to embed

more powerful special-purpose image-processing chips in the mouse

itself. This advance enabled the mouse to detect relative motion on a

wide variety of surfaces, translating the movement of the mouse into

the movement of the pointer and eliminating the need for a special

mouse-pad. This advance paved the way for widespread adoption of

optical mice. Optical mice illuminate the surface that they track over,

using an LED or a laser diode. Changes between one frame and the next

are processed by the image processing part of the chip and translated

into movement on the two axes using an optical flow estimation

algorithm. For example, the Avago Technologies ADNS-2610 optical mouse

sensor processes 1512 frames per second: each frame consisting of a

rectangular array of 18×18 pixels, and each pixel can sense 64

different levels of gray.

Laser mice

The laser mouse uses an infrared laser diode instead of an LED to
illuminate the surface beneath their sensor. As early as 1998, Sun
Microsystems provided a laser mouse with their Sun SPARCstation servers
and workstations.[20] However, laser mice did not enter the mainstream
market until 2004, when Logitech, in partnership with Agilent

Technologies, introduced its MX 1000 laser mouse.[21] This mouse uses a

small infrared laser instead of an LED and has significantly increased

the resolution of the image taken by the mouse. The laser enables

around 20 times more surface tracking power to the surface features

used for navigation compared to conventional optical mice, via

interference effects. While the implementation of a laser slightly

increases sensitivity and resolution, the main advantage comes from

power usage.

Power-saving in optical mice

Manufacturers often engineer their optical mice — especially

battery-powered wireless models — to save power when possible. In order

to do this, the mouse blinks the laser or LED when in standby-mode

(Each mouse has a different standby time). This function may also

increase the laser / LED life. Mice designed specifically for gamers,

such as the Logitech G5 or the Razer Copperhead, often lack this

feature in an attempt to reduce latency and to improve responsiveness.

Optical versus mechanical mice

The Logitech iFeel optical mouse uses a red LED to project light onto

the tracking surface.Unlike mechanical mice, which can become clogged

with lint, optical mice have no rolling parts; therefore, they do not

require maintenance other than removing debris that might collect under

the light emitter. However, they generally cannot track on glossy and

transparent surfaces, including some mouse-pads, sometimes causing the

cursor to drift unpredictably during operation. Mice with less

image-processing power also have problems tracking fast movement,

though high-end mice can track at 2 m/s (80 inches per second) and

faster.

Some models of laser mice can track on glossy and transparent surfaces,

and have a much higher sensitivity than either their mechanical or

optical counterparts. Such models of laser mice cost more than LED

based or mechanical mice.

As of 2006, mechanical mice have lower average power demands than their

optical counterparts. This typically has no practical impact for users

of cabled mice (except possibly those used with battery-powered

computers, such as notebook models), but has an impact on

battery-powered wireless models.

Optical models will outperform mechanical mice on uneven, slick, soft,

sticky, or loose surfaces, and generally in mobile situations lacking

mouse pads. Because optical mice render movement based on an image

which the LED illuminates, use with multi-colored mouse pads may result

in unreliable performance; however, laser mice do not suffer these

problems and will track on such surfaces. The advent of affordable

high-speed, low-resolution cameras and the integrated logic in optical

mice provides an ideal laboratory for experimentation on

next-generation input-devices. Experimenters can obtain low-cost

components simply by taking apart a working mouse and changing the

optics or by writing new software.

Inertial mice

Inertial mice use a tuning fork or other accelerometer (US Patent

4787051) to detect movement for every axis supported. Usually cordless,

they often have a switch to deactivate the movement circuitry between

use, allowing the user freedom of movement without affecting the

pointer position. A patent for an inertial mouse claims that such mice

consume less power than optically based mice, and offer increased

sensitivity, reduced weight and increased ease-of-use.

3D mice

Also known as flying mice, bats, or wands, these devices generally

function through ultrasound. Probably the best known example would be

3DConnexion/Logitech's SpaceMouse from the early 1990s.

In the late 1990s Kantek introduced the 3D RingMouse. This wireless

mouse was worn on a ring around a finger, which enabled the thumb to

access three buttons. The mouse was tracked in three dimensions by a

base station.Despite a certain appeal, it was finally discontinued

because it did not provide sufficient resolution.

A recent consumer 3D pointing device is the Wii Remote. While primarily

a motion-sensing device (that is, it can determine its orientation and

direction of movement), Wii Remote can also detect its spatial position

by comparing the distance and position of the lights from the IR

emitter using its integrated IR camera (since the nunchuk lacks a

camera, it can only tell its current heading and orientation). The

obvious drawback to this approach is that it can only produce spatial

coordinates while its camera can see the sensor bar.

Double mouse

Double mouse allow for two mice to be used by both hands as input

devices such as when operating various graphics and multimedia

applications.

Connectivity and communication protocols

To transmit their input, typical cabled mice use a thin electrical cord

terminating in a standard connector, such as RS-232C, PS/2, ADB or USB.

Cordless mice instead transmit data via infrared radiation (see IrDA)

or radio (including Bluetooth or WiFi), although many such cordless

interfaces are themselves connected through the aforementioned wired

serial buses.

While the electrical interface and the format of the data transmitted

by commonly available mice is currently standardized on USB, in the

past it varied between different manufacturers. A bus mouse used a

dedicated interface card for connection to an IBM PC or compatible

computer.

Serial interface and protocol

Standard PC mice once used the RS-232C serial port via a D-subminiature
connector, which provided power to run the mouse's circuits as well as

data on mouse movements. The Mouse Systems Corporation version used a

five-byte protocol and supported three buttons. The Microsoft version

used an incompatible three-byte protocol and only allowed for two

buttons. Due to the incompatibility, some manufacturers sold serial

mice with a mode switch: "PC" for MSC mode, "MS" for Microsoft

mode.

PS/2 interface and protocol

With the arrival of the IBM PS/2 personal-computer series in 1987, IBM

introduced the eponymous PS/2 interface for mice and keyboards, which

other manufacturers rapidly adopted. The most visible change was the

use of a round 6-pin mini-DIN, in lieu of the former 5-pin connector.

In default mode (called stream mode) a PS/2 mouse communicates motion,

and the state of each button, by means of 3-byte packets.[28] For any

motion, button press or button release event, a PS/2 mouse sends, over

a bi-directional serial port, a sequence of three bytes, with the

following format:

Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0
Byte 1 YV XV YS XS 1 MB RB LB
Byte 2 X movement
Byte 3 Y movement

Here, XS and YS represent the sign bits of the movement vectors, XV and

YV indicate an overflow in the respective vector component, and LB, MB

and RB indicate the status of the left, middle and right mouse buttons

(1 = pressed). PS/2 mice also understand several commands for reset and

self-test, switching between different operating modes, and changing

the resolution of the reported motion vectors.

IntelliMouse and others

A Microsoft IntelliMouse relies on an extension of the PS/2 protocol:

the ImPS/2 or IMPS/2 protocol (the abbreviation combines the concepts

of "IntelliMouse" and "PS/2"). It initially operates in standard PS/2

format, for backwards compatibility. After the host sends a special

command sequence, it switches to an extended format in which a fourth

byte carries information about wheel movements. The IntelliMouse

Explorer works analogously, with the difference that its 4-byte packets

also allow for two additional buttons (for a total of five).

The Typhoon mouse uses 6-byte packets which can appear as a sequence of

two standard 3-byte packets, such that ordinary PS/2 driver can handle

them.

Mouse-vendors also use other extended formats, often without providing

public documentation.

For 3D or 6DOF input, vendors have made many extensions both to the

hardware and to software. In the late 90's Logitech created ultrasound

based tracking which gave 3D input to a few millimeters accuracy, which

worked well as an input device but failed as a money making product.

Apple Desktop Bus

Apple Macintosh Plus mice, 1986.In 1986 Apple first implemented the

Apple Desktop Bus allowing the daisy-chaining together of up to 16

devices, including arbitrarily many mice and other devices on the same

bus with no configuration whatsoever. Featuring only a single data pin,

the bus used a purely polled approach to computer/mouse communications

and survived as the standard on mainstream models (including a number

of non-Apple workstations) until 1998 when iMac began the industry-wide

switch to using USB. Beginning with the "Bronze Keyboard" PowerBook G3

in May 1999, Apple dropped the external ADB port in favor of USB, but

retained an internal ADB connection in the PowerBook G4 for

communication with its built-in keyboard and trackpad until early 2005.

Tactile mice

In 2000, Logitech introduced the "tactile mouse", which contained a
small actuator that made the mouse vibrate. Such a mouse can augment

user-interfaces with haptic feedback, such as giving feedback when

crossing a window boundary. To surf by touch requires the user to be

able to feel depth or hardness; this ability was realized with the

first electrorheological tactile mice[31] but never marketed.

Other unusual variants have included a mouse that a user holds freely

in the hand, rather than on a flat surface, and that detects six

dimensions of motion (the three spatial dimensions, plus rotation on

three axes). Its vendor marketed it for business presentations in which

the speaker stands or walks around. So far, these mice have not

achieved widespread popularity.


Buttons

In contrast to the motion-sensing mechanism, the mouse's buttons have
changed little over the years, varying mostly in shape, number, and

placement. Engelbart's very first mouse had a single button; Xerox PARC

soon designed a three-button model, but reduced the count to two for

Xerox products. After experimenting with 4-button prototypes Apple

reduced it back to one button with the Macintosh in 1984, while Unix

workstations from Sun and others used three buttons. OEM bundled mice

usually have between one and three buttons, although in the aftermarket

many mice have always had five or more.


Apple Mighty Mouse with capacitance triggered buttonsThe three-button

scrollmouse has become the most commonly available design. As of 2007

(and roughly since the late 1990s), users most commonly employ the

second button to invoke a contextual menu in the computer's software

user interface, which contains options specifically tailored to the

interface element over which the mouse pointer currently sits. By

default, the primary mouse button sits located on the left-hand side of

the mouse, for the benefit of right-handed users; left-handed users can

usually reverse this configuration via software.

On systems with three-button mice, pressing the center button (a middle

click) typically opens a system-wide noncontextual menu. In the X

Window System, middle-clicking by default pastes the contents of the

primary buffer at the pointer's position. Many users of two-button mice

emulate a three-button mouse by clicking both the right and left

buttons simultaneously.

Additional buttons

Aftermarket manufacturers have long built mice with five or more

buttons. Depending on the user's preferences and software environment,

the extra buttons may allow forward and backward web-navigation,

scrolling through a browser's history, or other functions, including

mouse related functions like quick-changing the mouse's

resolution/sensitivity. As with similar features in keyboards, however,

not all software supports these functions. The additional buttons

become especially useful in computer games, where quick and easy access

to a wide variety of functions (for example, weapon-switching in

first-person shooters) can give a player an advantage. Because software

can map mouse-buttons to virtually any function, keystroke, application

or switch, extra buttons can make working with such a mouse more

efficient and easier.

In the matter of the number of buttons, Douglas Engelbart favored the

view "as many as possible". The prototype that popularised the idea of

three buttons as standard had that number only because "we could not

find anywhere to fit any more switches".

Wheels

The scroll wheel, a notably different form of mouse-button, consists of

a small wheel that the user can rotate to provide immediate

one-dimensional input. Usually, this input translates into "scrolling"

up or down within the active window or GUI-element . The scroll wheel

can provide convenience, especially when navigating a long document.

The scroll wheel nearly always includes a third (center) button. Under

many Microsoft Windows applications, appropriate pressure on the wheel

activates autoscrolling, and in conjunction with the control key (Ctrl)

may give the capability of zooming in and out; applications that

support this feature include Adobe Reader, Microsoft Word, Internet

Explorer, Opera, Mozilla Firefox and Mulberry. Some applications also

allow the user to scroll left and right by pressing the shift key while

using the mouse wheel.

Note that scrollwheels almost always function more as two switches,

rotating only in discrete "clicks" rather than actually acting as a

third analog axis.

Manufacturers may refer to scroll-wheels by different names for

branding purposes; Genius, for example, usually brand their

scroll-wheel-equipped products "Netscroll".

Mouse Systems introduced the scroll-wheel commercially in 1995,[32]

marketing it as the Mouse Systems ProAgio and Genius EasyScroll.

However, mainstream adoption of the scroll wheel mouse did not occur

until Microsoft released the Microsoft IntelliMouse in 1996. It became

a commercial success in 1997 when their Microsoft Office application

suite and their Internet Explorer browser started supporting its

wheel-scrolling feature.[33] Since then the scroll wheel has become a

standard feature of many mouse models.

Some mouse models have two wheels, separately assigned to horizontal

and vertical scrolling. Designs exist which make use of a "rocker"

button instead of a wheel — a pivoting button that a user can press at

the top or bottom, simulating "up" and "down" respectively. A peculiar

early example was a mouse by Saitek which had a joystick-style

hatswitch on it.

A more recent form of mouse wheel is the tilt-wheel. Tilt wheels are

essentially conventional mouse wheels that have been modified with a

pair of sensors articulated to the tilting mechanism. These sensors are

mapped, by default, to horizontal scrolling.

A third variety of built-in scrolling device, the scroll ball,

essentially consists of a trackball embedded in the upper surface of

the mouse. The user can scroll in all possible directions in very much

the same way as with the actual mouse, and in some mice, can use it as

a trackball. Mice featuring a scroll ball include Apple's Mighty Mouse

and the IOGEAR 4D Web Cruiser Optical Scroll Ball Mouse. IBM's

ergonomics laboratory designed a mouse with a pointing stick in it,[34]

envisioned to be used for scrolling, zooming or (with appropriate

software) controlling a second mouse cursor.

Button techniques

Rollover
Drag
Click
(left) Single-click
(left) Double-click
(left) Triple-click
Right-click
Rocker
Combination of right-click then left-click or keyboard letter
Combination of left-click then right-click or keyboard letter
Combination of left or right-click and the mouse wheel

Common button operations

Select
Launch an application
Display a menu
Drag and drop
Cut/copy to the clipboard
Paste from the clipboard

Mouse speed

The computer industry often measures mouse sensitivity in terms of

counts per inch (CPI), commonly expressed less correctly as dots per

inch (DPI) — the number of steps the mouse will report when it moves

one inch. In early mice, this specification was called pulses per inch

(ppi).If the default mouse-tracking condition involves moving the

pointer by one screen-pixel or dot on-screen per reported step, then

the CPI does equate to DPI: dots of pointer motion per inch of mouse

motion. The CPI or DPI as reported by manufacturers depends on how they

make the mouse; the higher the CPI, the faster the pointer moves with

mouse movement. However, software can adjust the mouse sensitivity,

making the cursor move faster or slower than its DPI. Current software

can change the speed of the pointer dynamically, taking into account

the mouse's absolute speed and the movement from the last stop-point.

Different software may name the settings "acceleration" or "speed" —

referring respectively to "threshold" and "pointer precision".

For simple software, when the mouse starts to move, the software will

count the number of "counts" received from the mouse and will move the

pointer across the screen by that number of pixels (or multiplied by a

factor f1=1,2,3). So, the pointer will move slowly on the screen,

having a good precision. When the movement of the mouse reaches the

value set for "threshold", the software will start to move the pointer

more quickly; thus for each number n of counts received from the mouse,

the pointer may move (f2 x n) pixels, where f2=2,3...10. Usually, the

user can set the value of f2 by changing the "acceleration" setting.

Operating systems sometimes apply acceleration, referred to as

"ballistics", to the motion reported by the mouse. For example,

versions of Windows prior to Windows XP doubled reported values above a

configurable threshold, and then optionally doubled them again above a

second configurable threshold. These doublings applied separately in

the X and Y directions, resulting in very nonlinear response. For

example one can see how the things work in Microsoft Windows NT.

Starting with Windows XP OS version of Microsoft and many OS versions

for Apple Macintosh, computers use a smoother ballistics calculation

that compensates for screen-resolution and has better linearity.

Etymology and plural

The first known publication of the word "mouse" is in Bill English's

1965 publication "Computer-Aided Display Control".

The Compact Oxford English Dictionary (third edition) and the fourth

edition of The American Heritage Dictionary of the English Language

endorse both computer mice and computer mouses as correct plural forms

for computer mouse. The form mice, however, appears most commonly,

while some authors of technical documents may prefer either mouse

devices or the more generic pointing devices. The plural mouses treats

mouse as a "headless noun."


Accessories

Mousepad

Englebart's original mouse did not require a mousepad;[36] the mouse

had two large wheels which could roll on virtually any surface.

However, most subsequent mice starting with the steel roller ball mouse

have needed mousepads in order to perform effectively.

The mousepad, the most common mouse accessory, appears most commonly in

conjunction with mechanical mice, because in order to roll smoothly,

the ball requires more friction than common desk surfaces usually

provide. So-called "hard mousepads" for gamers or optical/laser mice

also exist.

Although most optical and laser mice do not require a pad, some users

find that using a mousepad provides more comfort and less jitter of the

pointer on the display.Whether to use a hard or soft

mousepad with an optical mouse is largely a matter of personal

preference. One exception occurs when the desk surface creates problems

for the optical or laser tracking. Other cases may involve keeping desk

or table surfaces free of scratches and deterioration; when the grain

pattern on the surface causes inaccurate tracking of the pointer, or

when the mouse-user desires a more comfortable mousing surface to work

on and reduced collection of debris under the mouse.

Foot covers

Mouse foot-covers (or foot-pads) consists of low-friction or polished

plastic. This makes the mouse glide with less resistance over a

surface. Some higher quality models have teflon feet to reduce friction

even further.

Mice in the marketplace

Around 1981 Xerox included mice with its Xerox Star, based on the mouse
used in the 1970s on the Alto computer at Xerox PARC. Sun Microsystems,

Symbolics, Lisp Machines Inc., and Tektronix also shipped workstations

with mice, starting in about 1981. Later, inspired by the Star, Apple

Computer released the Apple Lisa, which also used a mouse. However,

none of these products achieved large-scale success. Only with the

release of the Apple Macintosh in 1984 did the mouse see widespread

use.

The Macintosh design, commercially successful and technically

influential, led many other vendors to begin producing mice or

including them with their other computer products (in 1985, Atari ST,

Commodore Amiga, Windows 1.0, and GEOS for the Commodore 64). The

widespread adoption of graphical user interfaces in the software of the

1980s and 1990s made mice all but indispensable for controlling

computers.

Alternative pointing devices

Trackball – the user rolls a ball mounted in a fixed base.

Touchpad – detects finger movement about a sensitive surface — the norm

for modern laptop computers. At least one physical button normally

comes with the touchpad, but users can also (configurably) generate a

click by tapping on the pad. Advanced features include detection of

finger pressure, and scrolling by moving one's finger along an edge.

Pointing stick – a pressure sensitive nub used like a joystick on

laptops, usually found between the g, h, and b keys on the keyboard.
Consumer touchscreen devices exist that resemble monitor shields.

Framed around the monitor, they use software-calibration to match

screen and cursor positions. Many firms that integrate touchscreen

equipment into existing displays and all-in-one devices (such as

portables PCs) for a reasonable fee are also in operation.

Mini-mouse – a small egg-sized mouse for use with laptop computers —

usually small enough for use on a free area of the laptop body itself.

It is generally optical, includes a retractable cord and uses a USB

port to save battery.

Palm mouse – held in the palm and operated with only two buttons; the

movements across the screen correspond to a feather touch, and pressure

increases the speed of movement.

Footmouse – a mouse variant for those who do not wish to or cannot use

the hands (see carpal tunnel) or the head; instead, it provides

footclicks.

Graphics tablet – a tablet with a pen or stylus used for pointing. The

user holds the device like a normal pen and moves it across a special

pad. The thumb usually controls the clicking via a two-way button on

the top of the pen, or by tapping.
Similar to a mouse is a puck, in which rather than tracking the speed

of the device, it tracks the absolute position of a point on the device

(typically a set of crosshairs painted on a transparent plastic tab

sticking out from the top of the puck). Pucks are typically used for

tracing in CAD/CAM/CAE work, and are often accessories for larger

graphics tablets.

Eyeball-controlled – A mouse controlled by the user's eyeball/retina

movements, allowing cursor-manipulation without touch.
Finger-mouse – An extremely small mouse controlled by two fingers only;

the user can hold it in any position

Gyroscopic mouse - A gyroscope senses the movement of the mouse as it

moves through the air. Users can operate a gyroscopic mouse when they

have no room for a regular mouse or must give commands while standing

up. This input device needs no cleaning and can have many extra

buttons, in fact, some laptops doubling as TVs come with gyroscopic

mice that resemble, and double as, remotes with LCD screens built in.
Some high-degree-of-freedom input devices

Applications of mice in user-interfaces

Computer-users usually utilize a mouse to control the motion of a

cursor in two dimensions in a graphical user interface. Clicking or

hovering can select files, programs or actions from a list of names, or

(in graphical interfaces) through pictures called "icons" and other

elements. For example, a text file might be represented by a picture of

a paper notebook, and clicking while the pointer hovers this icon might

cause a text editing program to open the file in a window. (See also

point-and-click)

Users can also employ mice gesturally; meaning that a stylized motion

of the mouse cursor itself, called a "gesture", can issue a command or

map to a specific action. For example, in a drawing program, moving the

mouse in a rapid "x" motion over a shape might delete the shape.

Gestural interfaces occur more rarely than plain pointing-and-clicking;

and people often find them more difficult to use, because they require

finer motor-control from the user. However, a few gestural conventions

have become widespread, including the drag-and-drop gesture, in which:

The user presses the mouse button while the mouse cursor hovers over an

interface object
The user moves the cursor to a different location while holding the

button down
The user releases the mouse button
For example, a user might drag-and-drop a picture representing a file

onto a picture of a trash-can, thus instructing the system to delete

the file.

Other uses of the mouse's input occur commonly in special

application-domains. In interactive three-dimensional graphics, the

mouse's motion often translates directly into changes in the virtual

camera's orientation. For example, in the first-person shooter genre of

games (see below), players usually employ the mouse to control the

direction in which the virtual player's "head" faces: moving the mouse

up will cause the player to look up, revealing the view above the

player's head.

When mice have more than one button, software may assign different

functions to each button. Often, the primary (leftmost in a

right-handed configuration) button on the mouse will select items, and

the secondary (rightmost in a right-handed) button will bring up a menu

of alternative actions applicable to that item. For example, on

platforms with more than one button, the Mozilla web browser will

follow a link in response to a primary button click, will bring up a

contextual menu of alternative actions for that link in response to a

secondary-button click, and will often open the link in a new tab or

window in response to a click with the tertiary (middle) mouse button.


One, two or three buttons?

One button mouseThe issue of whether pack-in bundled mice "should" have

exactly one button or more than one has attracted an enormous amount of

controversy. From the first Macintosh until late 2005 Apple shipped

every computer with a single-button mouse, whereas most other platforms

used multi-button mice. Apple and its advocates promoted single-button

mice as more user-friendly, and portrayed multi-button mice as

confusing for novice users. The Macintosh user interface, by design,

always has and still does make all functions available with a

single-button mouse. Apple's Human Interface Guidelines still specify

that all software-providers need to make functions available with a

single button mouse. However, X Window System applications, which Mac

OS X can also run, have developed with the use of two-button or even

three-button mice in mind, causing even simple operations like "cut and

paste" to become awkward.

While there has always been an aftermarket for mice with two, three, or

more buttons among experienced Macintosh users and extensive

configurable support to complement such devices in all major software

packages on the platform, Mac OS X shipped with hardcoded support for

multi-button mice. On August 2, 2005, Apple introduced their Mighty

Mouse multi-button mouse, which has four independently-programmable

buttons and a trackball-like "scroll ball" which allows the user to

scroll in any direction. Since the mouse uses touch-sensitive

technology, users can treat it as a one-, two-, three-, or four-button

mouse, as desired.

Advocates of multiple-button mice argue that support for a

single-button mouse often leads to clumsy workarounds in interfaces

where a given object may have more than one appropriate action. One

workaround was the double click, first used on the Apple Lisa, to allow

both the "select" and "open" operation to be performed with a single

button. Several common workarounds exist, and some are specified by the

Apple Human Interface Guidelines.


Three-button mouseOne such workaround (that favored on Apple platforms)

has the user hold down one or more keys on the keyboard before pressing

the mouse button (typically control on a Macintosh for contextual

menus). This has the disadvantage that it requires that both the user's

hands be engaged. It also requires that the user perform actions on

completely separate devices in concert; that is, holding a key on the

keyboard while pressing a button on the mouse. This can be a difficult

task for a disabled user, although can be remedied by allowing keys to

stick so that they do not need to be pressed down.

Another involves the press-and-hold technique. In a press-and-hold, the

user presses and holds the single button. After a certain period,

software perceives the button press not as a single click but as a

separate action. This has two drawbacks: first, a slow user may

press-and-hold inadvertently. Second, the user must wait for the

software to detect the click as a press-and-hold, otherwise the system

might interpret the button-depression as a single click. Furthermore,

the remedies for these two drawbacks conflict with each other: the

longer the lag time, the more the user must wait; and the shorter the

lag time, the more likely it becomes that some user will accidentally

press-and-hold when meaning to click. Studies have found all of the

above workarounds less usable than additional mouse buttons for

experienced users.

Most machines running Unix or a Unix-like operating system run the X

Window System which almost always encourages a three-button mouse. X

numbers the buttons by convention. This allows user instructions to

apply to mice or pointing devices that do not use conventional button

placement. For example, a left handed user may reverse the buttons,

usually with a software setting. With non-conventional button

placement, user directions that say "left mouse button" or "right mouse

button" are confusing. The ground-breaking Xerox Parc Alto and Dorado

computers from the mid-1970s used three-button mice, and each button

was assigned a color. Red was used for the left (or primary) button,

yellow for the middle (secondary), and blue for the right (meta or

tertiary). This naming convention lives on in some SmallTalk

environments, such as Squeak, and can be less confusing than the right,

middle and left designations.

Acorn's RISC OS based computers necessarily use all three mouse buttons

throughout their WIMP based GUI. RISC OS refers to the three buttons

(from left to right) as Select, Menu and Adjust. Select functions in

the same way as the "Primary" mouse button in other operating systems.

Menu will bring up a context-sensitive menu appropriate for the

position of the mouse pointer, and this often provides the only means

of activating this menu. This menu in most applications equates to the

"Application Menu" found at the top of the screen in Mac OS, and

underneath the window title under Microsoft Windows. Adjust serves for

selecting multiple items in the "Filer" desktop, and for altering

parameters of objects within applications — although its exact function

usually depends on the programmer.


Mice in gaming

Mice often function as an interface for PC-based computer games and

sometimes for video game consoles. They often appear in combination

with the keyboard.


First-person shooters

Logitech G5 Laser Mouse designed for gaming.Due to the cursor-like

nature of the crosshairs in shooter games, a combination of mouse and

keyboard provides a popular way to play first-person shooter (FPS)

games. Players use the X-axis of the mouse for looking (or turning)

left and right, leaving the Y-axis for looking up and down. The left

button usually controls primary fire. Many gamers prefer this over a

gamepad or joystick because it allows them to look around easily,

quickly and accurately and also as a consequence aim without auto-aim

assist. If the game supports multiple fire-modes, the right button

often provides secondary fire from the selected weapon. Secondary

weapons include grenades, knives, etc. The right button may also

provide bonus options for a particular weapon, such as allowing access

to the scope of a sniper rifle or allowing the mounting of a bayonet or

silencer or sometimes even jumping.

Gamers can use a scroll wheel for changing weapons, or for controlling

scope-zoom magnification. On most FPS games, programming may also

assign more functions to additional buttons on mice with more than

three controls. A keyboard usually controls movement (for example,

WASD, for moving forward, left, backward and right, respectively) and

other functions such as changing posture. Since the mouse serves for

aiming, a mouse that tracks movement accurately and with less lag

(latency) will give a player an advantage over players with less

accurate or slower mice.

An early technique of players, circle-strafing, saw a player

continuously strafing while aiming and shooting at an opponent by

walking in circle around the opponent with the opponent at the center

of the circle. Players could achieve this by holding down a key for

strafing while continuously aiming the mouse towards the opponent.

Games using mice for input have such a degree of popularity that many

manufacturers, such as Logitech, and Razer USA Ltd, make peripherals

such as mice and keyboards specifically for gaming. Such devices

frequently feature (in the case of mice) adjustable weights,

high-resolution optical or laser components, additional buttons,

ergonomic shape, and other features such as adjustable DPI.


Invert mouse setting

Many games, such as first- or third-person shooters, have a setting

named "invert mouse" or similar (not to be confused with "button

inversion", sometimes performed by left-handed users) which allows the

user to look downward by moving the mouse forward and upward by moving

the mouse backward (the opposite of non-inverted movement). This

control system resembles that of aircraft control sticks, where pulling

back causes pitch up and pushing forward causes pitch down; computer

joysticks also typically emulate this control-configuration.

After id Software's Doom, the game that popularized FPS games but which

did not support vertical aiming with a mouse (the y-axis served for

forward/backward movement), competitor 3D Realms' Duke Nukem 3D became

one of the first games that supported using the mouse to aim up and

down. It and other games using the Build engine had an option to invert

the Y-axis. The "invert" feature actually made the mouse behave in a

manner that users now regard as non-inverted (by default, moving mouse

forward resulted in looking down). Soon after, id Software released

Quake, which introduced the invert feature as users now know it. Other

games using the Quake engine have come on the market following this

standard, likely due to the overall popularity of Quake.

Home consoles

In 1988 the educational video game system, the VTech Socrates, featured

a wireless mouse with an attached mouse pad as an optional controller

used for some games. In the early 1990s the Super Nintendo

Entertainment System video game system featured a mouse in addition to

its controllers. The Mario Paint game in particular used the mouse's

capabilities, as did its successor on the N64. Sony Computer

Entertainment released an official mouse product for the PlayStation

console, and included one along with the Linux for PlayStation 2 kit.

However, users can attach virtually any USB mouse to the PlayStation 2

console. In addition the PlayStation 3, and Xbox 360 also support USB

mice. Recently the Wii also has this latest development added on in a

recent software update.