Biliary tract includes gallbladder and bile ducts

Within the liver, small biliary channels known as bile ductules join together to form the smaller bile ducts, which ultimately form right and left hepatic ducts, exit the liver, which in turn join to form common hepatic duct (CHD) 

Gall bladder is a pear shaped organ, situated below the liver

Bile secreted from the liver flows through the bile ducts 

Cystic duct of the gallbladder joins the common hepatic duct to form common bile duct (CBD)

CBD joins the main pancreatic duct (MPD) at the lower end and the common channel enters into the 2nd part of duodenum

Gall Bladder concentrates the bile and releases during food ingestion 

Bile and pancreatic juices are released into the duodenum at the time of meal, which helps in digestion and absorption of food nutrients especially fat and fat soluble vitamins