This introductory chapter gives an overview of the key concepts discussed in the subsequent chapters of this book. Research has shown that individuals can act like lay scientists under certain conditions. Importantly, individuals seem to be quite flexible in their strategies when constructing subjective social reality. Social cognition researchers investigate how individuals mentally construct social reality because they believe that social behavior, rather than being directly determined by the external stimulus of a situation, is mediated by the internal mental representation of that situation. Social cognitive processing is also different from the processing of inanimate targets because there is a strong link between the way most individuals think about their social world and the way they think about themselves, that is, their self-conception. Social cognition is unique in several ways. Most importantly, unlike other judgments, social judgments usually refer to non-observable attributes, rendering social cognition a highly complex endeavor.