When we design for humans, we need to understand how humans understand the objects, services, and the world around them. The understanding of how people think about how things work is called a mental model.
How does a toaster work? You most certainly do not have a degree in mechanics or engineering and have never built a toaster. Nevertheless, you have a model in your head that explains for you how it works. This is what we call a mental model.
This model has an impact on the expectations you have about your toaster and shapes your interaction with it. This notion of mental model is later also used in the world of design and research with publications like Indi Young’s “Mental Models, Aligning Design Strategy with Human Behavior” that we will cover later in this booklet.
The term mental model seems to have first appeared in 1943. It was coined by Kenneth Craik in his book “The Nature of Explanation”.
Going further
This article is part of the book "A Tiny History of Service Design, " a tiny two-hour read that goes through the historical events that created what Service Design is today.