PC Hardware in a Nutshell, Second Edition

Chapter 20. Mice and Trackballs

Mice and trackballs are members of a class generically described as pointing devices. All pointing devices have the same purpose—allowing you to move the cursor (or pointer) around the screen and to click to select items or perform other functions. A great variety of fiendishly clever pointing devices are built into notebook computers, but nearly all desktop systems use mice. Those few that don’t use a trackball, which is essentially a mouse turned on its back, with the roller ball accessible.

Mice Versus Trackballs

As with any input device, personal preference should rule choice. That said, relative to mice, trackballs have the following advantages:

• A trackball remains in place, and so requires less free desk space than a mouse.

• The trackball roller ball contacts your thumb rather than the desktop or mouse pad, which means it is less likely to require frequent cleaning. (However, the new “red-light” optical mice do not require cleaning and so eliminate this advantage.)

• A trackball is often the better choice for 3D gaming and similar programs, where pointing and clicking are the most important functions.

• Some evidence suggests that using a trackball is less likely to cause RSI than using a mouse.

And the following disadvantages:

• Most trackballs are designed such that you guide the pointer with your thumb, which is the least dexterous digit. Accordingly, many users find it harder to position the cursor exactly with a trackball than with a mouse. ...