Cholangiocyte biology is a dedicated field of study focused on the epithelial cells lining the bile ducts, known as cholangiocytes. This research area investigates their complex development, diverse functions, underlying molecular mechanisms, and their critical roles in both biliary system homeostasis and the pathogenesis of bile duct diseases. It serves as a fundamental basis for understanding biliary physiology, developing experimental models for cholangiopathies, and identifying potential diagnostic and therapeutic targets.