This chapter, authored by Kawachi, Subramanian, and Almeida-Filho, provides a glossary addressing eight key questions about health inequalities. The authors clarify the distinction between health inequality and health inequity, discussing the role of poverty versus socioeconomic gradients in generating health inequalities. They explore whether health inequalities are mediated by material deprivation or psychosocial mechanisms, and whether relative income affects health independently of absolute income. The chapter also examines the impact of place on health inequalities and the contribution of the life course to health disparities. Additionally, it discusses the importance of studying various types of inequalities beyond socioeconomic groups, such as gender and race. The authors emphasize the need for a multifaceted approach to understanding and addressing health inequalities, highlighting the complexity and interplay of various factors.This chapter, authored by Kawachi, Subramanian, and Almeida-Filho, provides a glossary addressing eight key questions about health inequalities. The authors clarify the distinction between health inequality and health inequity, discussing the role of poverty versus socioeconomic gradients in generating health inequalities. They explore whether health inequalities are mediated by material deprivation or psychosocial mechanisms, and whether relative income affects health independently of absolute income. The chapter also examines the impact of place on health inequalities and the contribution of the life course to health disparities. Additionally, it discusses the importance of studying various types of inequalities beyond socioeconomic groups, such as gender and race. The authors emphasize the need for a multifaceted approach to understanding and addressing health inequalities, highlighting the complexity and interplay of various factors.