Popular psychology refers to concepts and theories about human mental life and behaviour that come from outside the technical study of psychology, but purport to go beyond everyday knowledge.
Popular psychology should be distinguished from naive psychology, the technical term for the intuitive, non-technical understanding of our own and others' psychological processes that all people have. Like the parallel areas of naive physics and naive biology, naive psychology may often be technically incorrect but is often functional, in the sense that it gives an accurate description of the situations that that we face as individuals, and specifies reasonable courses of action to take.
Popular psychology, on the other hand, usually purports to offer a technical insight, and often uses technical jargon, but does so in a way that is unsupported by systematic analysis or knowledge. Often it draws on academic or clinical psychology, but seizes on ideas out of context or without the conditions and cautions that a professional psychologist would attach to them.
Popular psychology should also be distinguished from various schools of psychological thinking that lie outside the current mainstream, for example the approaches to understanding psychology that flow from most religious systems or from astrology. While professional psychologists are as mistrustful of these as they are of popular psychology, some of these systems do represent a disciplined and careful attempt to understand human thought and emotions.