Loneliness is a subjective feeling of social isolation or lack of connection with others. It is a common human emotion that may be experienced by people of all ages, backgrounds, and walks of life. Research on loneliness examines the causes, consequences, and potential interventions to address this feeling of disconnectedness. Loneliness has been linked to negative physical and mental health outcomes, including depression, anxiety, and increased risk of mortality. Understanding loneliness is important for developing strategies to promote social connectedness and well-being in individuals and communities.