Designed for Use, 2nd Edition

What People Think

The concept a user forms about how something works is called a mental model. Mental models are usually much simpler than reality. In About Face [Coo95], Alan Cooper refers to mental models as “a cognitive shorthand (...), one that is powerful enough to cover [the user’s] interactions with [the product], but which doesn’t necessarily reflect its actual inner mechanics.”

Jakob Nielsen says, “A mental model is what the user believes about the system at hand.”^[40]

Here’s an example. Somebody driving a car might think there is a direct mechanical connection between the gas pedal and the engine, assuming that pushing down on the gas pedal opens some sort of valve that causes more fuel to enter the engine, thus making the car run faster. ...