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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).[8] 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"[34]

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


Main article: Mousepad

Englebart's original mouse did not require a mousepad;[35] the mouse had two large wheels which could roll on virtually any surface. However, most subsequent mouses 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.[citation needed] 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.[citation needed]


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.

  • 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

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