A mental model is a mechanism of thought by which a human being, or other animal, attempts to explain how the real world works.

It is a type of internal symbol or representation of external, hypothetical reality that plays an important role in cognition.

A mental model is not factual: it is only based on beliefs and predictions that come from the user’s previous experiences. Thus, each user has different mental models.

The concept is first picked up in “The nature of Explanation”, Kenneth Craik (1943), to refer to the “representations” that explain a person’s thoughts and behaviors.