A mummy is the body of a person (or an animal) that has been preserved after death. Normally when we die, bacteria and other germs eat away at the soft tissues (such as skin and muscles) leaving only the bones behind. Since bacteria need water in order to grow, mummification usually happens if the body dries out quickly after death. The body may then be so well preserved that we can even tell how the dead person may have looked in life.

Mummies are made naturally or by embalming, which is any process that people use to help preserve a dead body. Mummies can be dried out by extreme cold, by the sun, by smoke, or using chemicals such as natron. Some bodies become mummies because there were favorable natural conditions when they died. Others were preserved and buried with great care.