Barium sulfate was first isolated in 1808 by English chemist Humphry Davy. It is a soft, metallic element normally found in nature as barium carbonate or barium sulfate. Barium sulfate was first used for medical imaging in 1910 in Germany. It appears as a fine white powder and is insoluble in water. Barium sulfate examinations are used to image the gastrointestinal tract. Single and double contrast techniques are used to image different parts of the stomach and duodenum. Advantages and disadvantages of each technique are provided. Indications for barium examinations include pain, diarrhea, anemia, partial obstruction, malabsorption and abdominal masses.