Canopic jars were an essential part of the ancient Egyptian mummification process. They were used to hold the internal organs that were removed from the body during the ritual, to enable them to be preserved. After said viscera were removed, they were washed with palm wine, soaked in natron, treated with hot resin and bandaged. They were then placed in the jars, which were sealed in a canopic chest and placed with the mummified body so that it could use them in the afterlife.
The jars were made from a variety of materials, ranging from wood, to stone and pottery. Their design became more ornate as time went on, and what started as jars sealed with simple lids in the days of the Old Kingdom (3000-2200 BC), developed so that the stoppers were in the rough form of human heads in the era of the Middle Kingdom (2200-1500 BC). By the time of the New Kingdom (1500-1000 BC), each stopper was carved in the image of one of the Sons of Horus. These were minor gods who had specific responsibility for each organ, and therefore were invoked to make sure it made it intact into the next world. They consisted of the falcon Qebhesenuef, who protects the intestines, Hapy the baboon who held the lungs, the jackal Duamutef who guarded the stomach, and the human Imsety who kept the liver.