Group psychology is a branch of psychology that focuses on the study of how individuals behave, think, and feel in groups. It examines the influence of group dynamics, social norms, roles, and interactions on individual behavior and cognition within a group context.

Key aspects of group psychology include:

1. Group Formation and Structure: Group psychology explores how groups form, develop, and maintain their structure over time. It examines the factors that influence group cohesion, such as shared goals, norms, values, and identity, as well as the role of leadership, communication patterns, and social roles within the group.
2. Social Influence and Conformity: Group psychology investigates how individuals are influenced by the presence and actions of others within a group. It examines social conformity, obedience to authority, groupthink, and other phenomena related to the impact of group norms and social pressure on individual behavior and decision-making.
3. Group Identity and Intergroup Relations: Group psychology examines how individuals define their sense of identity and belonging within a group, as well as the dynamics of intergroup relations and conflicts. It explores the formation of ingroups and outgroups, stereotypes, prejudice, discrimination, and strategies for promoting positive intergroup relations.
4. Leadership and Power Dynamics: Group psychology studies the role of leadership and power dynamics within groups. It explores different leadership styles, traits of effective leaders, and the influence of leadership on group cohesion, motivation, and performance. It also examines the distribution of power within groups and the consequences of power imbalances on group dynamics.
5. Group Decision-Making: Group psychology investigates how groups make decisions, solve problems, and reach consensus. It examines factors that affect the quality of group decision-making, such as group size, communication patterns, decision-making processes, and the presence of dissenting voices. It also explores techniques for improving group decision-making, such as brainstorming, consensus building, and decision support systems.
6. Social Facilitation and Social Loafing: Group psychology explores the effects of social facilitation and social loafing on individual performance within groups. It examines how the presence of others can enhance or impair individual performance on tasks, depending on factors such as task complexity, accountability, and social comparison processes.
7. Group Therapy and Interventions: Group psychology has applications in clinical psychology and counseling through group therapy interventions. It uses group dynamics to facilitate therapeutic change, promote social support, and enhance interpersonal skills among group members. It also provides a forum for exploring interpersonal issues, practicing new behaviors, and fostering empathy and understanding.

Overall, group psychology offers valuable insights into the complexities of human social behavior and interaction within group contexts. It informs our understanding of how groups influence individual behavior, cognition, and emotions and has applications in various domains, including social psychology, organizational behavior, counseling, and community development.