One of the most dramatic demonstrations of the role of the mind in one's apprehension of the world is the existence of cognitive biases. This chapter presents a three‐category framework for understanding cognitive biases from an evolutionary perspective. It describes the implications of this evolutionary psychological perspective on biases. The chapter proposes that analogous logic may be applied to understanding cognitive biases. Cognitive biases can arise for three reasons: Selection may discover useful shortcuts that tend to work in most circumstances, though they fall short of some normative standards (heuristics); biases can arise if biased solutions to adaptive problems resulted in lower error costs than unbiased ones (error management biases); and apparent biases can arise if the task at hand is not one for which the mind is designed (artifacts). The chapter discusses two general categories of artifact effects: evolutionarily invalid problem formats and evolutionarily invalid problem content.