Pointing without sliding a device
A mouse needs a flat surface to slide across. That requirement is easy to meet at an office desk and awkward almost everywhere else. Over several decades, designers developed a range of alternatives that let a person move a pointer while the device itself stays still. The main ones are the trackball, the pointing stick and the touchpad. They share a purpose with the mouse, but they grew from different needs and found different homes.
Trackballs
A trackball is, in effect, a mouse turned upside down. A ball sits in a socket and is rolled with the fingers or the palm, while the body of the device stays put. The principle is old. Descriptions of ball-based position controllers appear in military display systems of the early 1950s, and it is frequently reported that one such device was built for a naval system at about that time. Details are not well documented, so it is safest to say the trackball was among the earliest pointing devices, and probably older than the mouse.
Trackballs found early use in places where a mouse was not practical. Air traffic control and radar rooms had little room on crowded consoles. Some computer-aided design stations used them for steady positioning. In arcades, trackballs were fitted to games such as Missile Command around 1980 and others of the era, letting players sweep a cursor across the screen quickly. For people who like them, trackballs have a reputation for being comfortable, since the arm stays still and only the thumb or fingers move, although the evidence about strain is mixed and varies by person.
In the 1990s, some portable computers included small built-in trackballs. Apple’s PowerBook 100 of 1991 placed one in front of the keyboard, and several other makers copied the idea. The ball tended to collect dust and lint and wear out, which helped to push designers toward other solutions.
Pointing sticks
The pointing stick is a small rubber nub placed among the keys of a laptop keyboard, often between the G, H and B keys. Pressure applied with a fingertip moves the pointer, with the speed depending on how hard the finger pushes. IBM made the design well known on its ThinkPad laptops in the early 1990s, and other manufacturers have used similar devices. A fan of the pointing stick values that the hands never leave the typing position. Others find it slow to learn, and it is less suited to quick, long moves across a screen.
Touchpads
The touchpad is a flat, touch-sensitive surface below the keyboard. Moving a finger across it moves the pointer, and tapping or pressing a button below it clicks. Several companies developed touchpads in the 1980s and early 1990s, and capacitive sensing technology made them compact and reliable. Apple’s PowerBook line brought the touchpad to a large audience in the mid-1990s, and other laptop makers adopted it soon after. By the end of the decade it had become the usual built-in pointing device on laptop computers, largely replacing the built-in trackball.
The reasons were practical. A touchpad has no moving parts that collect dirt, takes up little room, can be made thin, and sits within easy reach of the typing hands.
Over time, touchpads gained abilities. Scrolling with two fingers, pinching to zoom and swiping between pages were added in the 2000s and 2010s, partly as the success of phones taught people to expect touch gestures. Larger pads, glass surfaces and pressure-sensitive designs followed. Some users still plug in a mouse for precise work or long sessions, which says something about how well a pad replaces a mouse for fine control.
Choosing between them
There is no universal winner. A rough guide to where each device is used follows.
| Device | Typical use | Main advantage | Main drawback |
|---|---|---|---|
| Trackball | Control rooms, some design work, accessibility, arcades | Stays in place; little desk space | Cleaning; takes time to learn |
| Pointing stick | Business laptops | Hands stay on keys | Slow for long moves |
| Touchpad | Nearly all laptops | Built in; no moving parts | Less precise for fine work |
Accessibility is a major reason these devices endure. People who find it hard to move the whole arm, or who have limited grip, may find a trackball or a pad easier to control than a mouse. Special large-ball trackballs and foot-operated or head-tracking devices also exist for people with specific needs.
What this tells us
Pointing devices are a reminder that there is rarely one best answer in interface design. The mouse became the standard for desks, but laptops, arcades, crowded consoles and accessibility needs all gave other devices a place. The trackball came first and kept finding niches, the pointing stick offered a keyboard-centered option, and the touchpad turned out to be the practical answer for portable machines. Touch screens now cover many of the same needs on phones and tablets, yet none of these devices has been completely abandoned.