The digestive system ingests food, breaks it down for nutrient absorption, and eliminates waste. It contains major organs like the liver, stomach, and pancreas. The liver performs many functions, including producing bile to break down fat and helping blood clotting and temperature regulation. Gallstones form when liquid in the gallbladder hardens into pieces and can cause pain, nausea, and other symptoms. Treatment may include drugs to dissolve stones or surgery to remove the gallbladder. Maintaining a healthy lifestyle can help prevent gallstones.