Mummies are dead people or animals whose skin and organs are preserved due to intentional or unintentional exposure to chemicals, extremely cold, extremely low humidity or insufficient air. Therefore, if they are kept cool, the recovered bodies will not be further decomposed and dried. Some authorities have limited the use of the term to bodies that were deliberately embalmed with chemicals, but the term can be used to cover bodies that were accidentally dried back to at least 1615.

Mummies of humans and other animals have been found on every continent, due to the protection of nature under abnormal conditions and as cultural relics. More than one million animal mummies have been found in Egypt, many of them cats. Many of Egypt's animal mummies are sacred Ibis. Radiocarbon dating shows that the mummies of the analyzed Ibis were between 450 and 250 BC.

In addition to the famous mummies in ancient Egypt, intentional mummies are the characteristics of several ancient cultures in the dry climate of America and Asia. The exact age of the Lingdong mummy in Fallon, Nevada, North America has exceeded 9400 years. Prior to the discovery, the earliest known intentional mummy was a child, one of the chinchorro mummies found in the Camarones Valley in Chile, dating back to 5050 BC. The oldest known body of a natural mummy is a decapitated skull, 6000 years old. It was found in 1936 in Inca Cueva No. 4, South America.