Variants of the Mouse

Although the mouse is a handy tool, some people do not like using a mouse or have difficulty maneuvering one. For others, a mouse requires too much desktop space—a real problem when you are not working at a desk!
For these reasons and others, hardware makers have developed devices that duplicate the mouse's functionality but interact with the user in different ways. The primary goals of these "mouse variants" are to provide case of use while taking up less space than a mouse. They all remain stationary and can even be built into the keyboard.


A trackball is a pointing device that works like an upside-down mouse. You rest your index finger or thumb on an exposed ball, then place your other fingers on the buttons. To move the pointer around the screen, you roll the ball with your index finger or thumb. Because you do not move the whole device, a trackball requires less space than a mouse. Trackballs gained popularity with the advent of laptop computers, which typically are used on laps or on small work surfaces that have no room for a mouse.
Computer mouse trackball.
Fig. 1: Computer mouse trackball.
Trackballs come in different models, as shown in Fig. 1. Some trackballs are large and heavy with a ball about the same size as a cue ball. Others are much smaller. Most trackballs feature two buttons, although three-button models are also available. Trackball units also are available in right- and left-handed models.


The trackpad (also called a touchpad) is a stationary pointing device that many people find less tiring to use than a mouse or trackball. The movement of a finger across a small touch-sensitive surface is translated into pointer movement on the computer screen. The touch-sensitive surface may be only 1.5 or 2 inches square, so the finger never has to move far. The trackpad's size also makes it suitable for a notebook computer. Some notebook models feature a built-in trackpad rather than a mouse or trackball (see Fig. 2).
Fig. 2: Modern notebook computers and desktop keyboards features a built-in trackpad.
Like mice, trackpads usually are separate from the keyboard in desktop computers and are attached to the computer through a cord. Some special keyboards feature built-in trackpads. This feature keeps the pad handy and frees a port that would otherwise be used by the trackpad.
Trackpads include two or three buttons that perform the same functions as mouse buttons. Some trackpads are also “strike sensitive," meaning you can tap the pad with your fingertip instead of using its buttons.

Pointers in the Keyboard

Many portable computers now feature a small joystick positioned near the middle of the keyboard, typically between the
keys. The
is controlled with either forefinger, and it controls the movement of the pointer on screen. Because users do not have to take their hands off the keyboard to use this device, they can save a great deal of time and effort. Two buttons that perform the same function as mouse buttons are just beneath the spacebar and are pressed with the thumb.
joystick in keyboard.
Fig. 3: joystick in keyboard.
Several generic terms have emerged for this device; many manufacturers refer to it as an integrated pointing device, while others call it a 3-D point stick. On the IBM ThinkPad line of notebook computers, the pointing device is called the TrackPoint (see Fig. 3).

Do you want to say or ask something?

Only 250 characters are allowed. Remaining: 250
Please login to enter your comments. Login or Signup .
Be the first to comment here!
Terms and Condition
Copyright © 2011 - 2024
Privacy Policy