Group disparities is the systematic and often persistent unequal distribution of resources, opportunities, and outcomes across distinct social groups defined by characteristics such as race, ethnicity, gender, socioeconomic status, or geographic location. As a central concept and field of academic inquiry, it involves the empirical investigation, measurement, and analysis of these differences to identify patterns, understand underlying causal mechanisms including systemic factors and historical legacies, and assess their societal consequences, thereby informing research, policy, and interventions aimed at promoting equity and reducing inequality.