What Is A Trackball?

Date First Published: 6th July 2023

Topic: Computer Systems

Subtopic: Computer Hardware

Article Type: Computer Terms & Definitions

Difficulty: Easy

Difficulty Level: 3/10

CONTENTS

Are Trackballs An Accessibility Device?
Disadvantages Of Trackballs
Who Invented The Trackball?

Learn about what a trackball is in this article.

A trackball is an input device that acts as an alternative to a mouse. It is made up of a moveable ball on the top that sits within the holder and can be rotated in any direction to move the cursor on the screen. Trackballs consist of a ball located in a socket which contains sensors to detect the rotation of the ball and determine how much the cursor moves with each rotation. Users rotate the ball using their thumb, fingers, or the palm of their hand and use their fingertips to press the buttons.

Like normal mouses, trackballs also include left and right click buttons. The left-click button is the main button used to select, move, and drag and drop items and the right-click button is used to provide additional information on a selected item. They don't include scroll wheels as pressing and holding the ball enables horizontal and vertical scrolling.

Trackballs also don't require a flat desk surface. This means that they can be used wirelessly from a sofa, outside, or on other uneven surfaces. This makes them useful when using a laptop on unstable platforms, like boats, where a rolling deck could lead to undesirable input. Some trackballs may also have textured rubber or metal services to provide extra grip.

Are Trackballs An Accessibility Device?

Trackballs make it easier for people with limited mobility to use as the ball can be fully rotated without physically moving the whole device, leaving less strain on the arms and wrist than a normal mouse. Although they are not specifically an assistive technology, trackballs are often used as an accessibility device for people who have difficulty using a normal mouse.

Disadvantages Of Trackballs

Some disadvantages of trackballs are:

They need to be regularly cleaned for the ball to continue running smoothly. Over time, the ball can become dirty or sticky, which will affect its performance. Trackballs require more cleaning and maintenance than mouses.
It can take some time to get used to using a trackball at first. Since mouses often feel more natural, not all users are familiar with trackballs, and trackballs require getting used to, mouses are more commonly used. Most computers have a mouse as the primary input device rather than a trackball.
Although it reduces strain on the arms and wrist, there is a higher chance of strain on the fingers since precise movements are only made with the fingers.
Although they both use the same technology, they are usually more expensive than mouses. This is because of the more advanced materials.

Who Invented The Trackball?

The first known trackball device was invented by Ralph Benjamin in 1946 when working for the British Royal Navy Scientific Service. Benjamin's project used analogue computers to calculate the future position of target aircraft based on several initial input points provided by a user with a joystick.

In 1946, Benjamin created the roller ball, a ball tracker system, in response to the need for a more elegant input device. The device was patented in 1947, but it was only ever manufactured as a prototype and was kept a military secret. The prototype used a metal ball rolling on two rubber-coated wheels. Production versions of the CDS used joysticks.