This document discusses the application of social psychology principles to various fields. It describes how social psychology can be applied to health psychology to understand health behaviors and develop intervention strategies. It also discusses several models used in health psychology, including the health belief model, theory of planned behavior, and stages of change model. The document notes social psychology can provide perspectives on chronic illness and contribute to improving healthcare systems. It also outlines how industrial and organizational psychology examines human behavior in workplace settings using psychological theories, focusing on topics like motivation and social perception.