Introduction Humans use information in everyday activities, including reading, driving, learning, planning and decision-making. There is broad agreement that, in some sense, human cognition involves the processing of information, and, indeed, many psychological and neuroscientific theories explain cognitive phenomena in information-theoretic terms. However, it is not always clear which of the many concepts of ‘information’ is the one relevant to understanding the nature of human cognition. The particular concept of ‘information’ we choose also has implications for what qualifies as information processing. In this chapter, we take the basic information-processing model, roughly along the lines of Richard Atkinson and Richard Shiffrin’s early Model of Human Memory (1971), to include (1) input, (2) processing, (3) storage, (4) retrieval and (5) output.