The Theory of Planned Behavior is a psychological model that explains how individual intentions influence behavior. It suggests that three key factors shape these intentions: attitudes toward the behavior, subjective norms, and perceived behavioral control. Attitudes refer to personal evaluations of the behavior, subjective norms involve social pressures or expectations, and perceived behavioral control relates to the belief in one's ability to perform the behavior. This theory is widely used in various fields, including health promotion and marketing, to predict how likely people are to engage in specific actions. By understanding these factors, interventions can be designed to encourage positive behaviors, such as exercise or healthy eating.