As an academic field, sociology enables learners to understand the structures, relationships, and processes that shape social life. It addresses key concerns such as inequality, social class, culture, gender, ethnicity, risk, and globalization. Psychology complements this perspective by examining human behaviour and mental processes through diverse theoretical and applied frameworks grounded in both classical thought and contemporary research. Psychological inquiry covers a broad range of areas including developmental, cognitive, social, biological, and applied psychology, along with psychometrics, individual differences, and research methodology. Both sociology and psychology belong to the behavioural and social sciences, employing approaches that span empirical investigation, theoretical analysis, and philosophical reflection. A central aim of these disciplines is the development of analytical thinking, problem-solving ability, and effective communication skills. This encyclopaedia provides a structured platform for exploring how social environments and individual factors interact to influence human behaviour, identity, and development. Intended for students, researchers, and academics, this work presents a consolidated overview of applied theories and contemporary research in sociology and psychology, offering valuable insight for those engaged in scholarly and practical inquiry.