This document provides an overview of the anatomy, embryology, histology, imaging, and physiology of the gallbladder and biliary tree. It describes the components of the extrahepatic biliary system including the gallbladder, cystic duct, common hepatic duct, and common bile duct. It discusses the formation of the gallbladder during embryological development and provides details on the structure and blood supply of the gallbladder and biliary tree. It also summarizes the function of bile in digestion and the neurohormonal regulation of bile secretion and gallbladder contraction.