With the invention of the ball mouse in 1972 by Bill English while working for Xerox, computer navigation was changed forever. Instead of external wheels (like a bona fide etch-a-sketch) you could use a single ball and control your cursor to travel in any direction. Soon, the trackball mouse came to pass allowing you to simply move your hand in any direction, including ergonomically placed buttons. These inventions were invented as tools to allow you to indirectly interface humans with a visual representation of 1s and 0s. So would the logical progression move to a more direct way of allowing humans to interface with computers sans the intermediary device?

It would seem that more and more major manufacturers are moving more and more to direct interfacing. Some popular examples of a movement towards touchscreens are the Apple iPhone, Nintendo DS, the Fujitsu Tablet PC, and the Toughbook series by Panasonic. But why are the vast majority of us still using a mouse while the most significant patents and advancements of touchscreen technology were filed during the 70s and 80s, the same time the mouse came to being?

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One obvious reason is the cost. Touchscreens are generally around double the cost of conventional monitors. But I'd submit that the main problem is simply with the ergonomics. There is a tremendous strain on human fingers and arms when required to select several different spots on a touchscreen. The hard surface of the screens also cause minor stress on the soft finger tips of humans. Use of a stylus or "pen" can be helpful, but problematic in public settings.

Touchscreens will still always have its own place in a world that is always striving for convenience and coherence. They will continue to be popular for functions that require only a minute of use to perform a task, such as automatic check-in kiosks at airports, Bank ATMs, and point-of-sale kiosks for retail. They will also always find their place in industrial settings where it is not convenient to have a mouse and keyboard at hand. But it is my belief that the vast majority of personal computers will continue to use intermediary devices to decrease the strain and range of motion a person must exert.