ingroupoutgroup

Ingroupoutgroup is a term used in social psychology to describe how people categorize others into groups they belong to (the in-group) and groups they do not belong to (the out-group). The distinction is often accompanied by a sense of affiliation with the in-group and distance from the out-group, shaping attitudes and behavior in everyday interactions. Membership can be based on ethnicity, nationality, religion, sports teams, or more arbitrary criteria in experimental settings. The concept helps explain why individuals may favor those who resemble or identify with them and may distrust or devalue those perceived as outsiders.

Origins and key ideas include social identity theory, which posits that people derive part of their self-concept from group membership and seek to enhance the status of their in-group. Research using the minimal group paradigm shows that even random Group assignments can produce in-group favoritism and out-group discrimination, suggesting that bias can arise from categorization itself rather than from real-world differences or threats.

Mechanisms and effects encompass stereotyping, preferential treatment, and derogatory judgments toward out-group members. This can contribute to prejudice, discrimination, and social distance, as well as intergroup conflict. Positive intergroup relations can occur when groups cooperate toward shared goals under conditions described by contact theory, including equal status, common goals, intergroup cooperation, and institutional support.

Contexts and nuance include the appearance of in-group/out-group dynamics in politics, education, workplaces, and interethnic relations. Identities are often fluid; individuals may belong to multiple groups, and boundary definitions can shift by context. Some critiques emphasize power imbalances in who defines the in-group and out-group, and note that reducing bias often requires structural as well as interpersonal changes.