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 naïve 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 naïve physics and naïve biology, naïve psychology may often be technically incorrect but is often functional, in the sense that it gives an accurate description of the situations 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. Many popular psychology concepts are taken from pseudoscience but may also refer to academic or clinical psychology, but the literature tends to seize 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, quackery and pseudoscience, a minority of these systems do represent some attempt to understand human thought and emotions.
Go into any bookstore and you will see shelves of self-help books, many of which promote a form of "poppsychology." Although these are bestsellers, they are filled with half-truths and myths.
William James, often considered the father of American psychology, defined self-esteem as "the sum of your successes and pretensions." In other words, your self-esteem is a reflection of how you are actually performing compared to how you think you should be performing.
As with many of these poppsychology myths, there is a kernel of truth.
If you browse the psychology section in any book store you will find books on multiple intelligence, emotional intelligence, personality typologies (such as the MBTI and the Enneagram), etc. Most of the available material is written by psychologists, adding at least a veneer of respectibility.
A person doing psychology research tends to want to publish in what are called peer-reviewed professional journals, where their article is critiqued and assessed prior to publication.
One of the scarier part of the "pop psych" trend is that many trainers and consultants believe that on the strength of reading a book or two, they can help you apply the concepts to your workplace.