Shapeshifting
Shapeshifting, transformation or transmogrification is a change in the form or shape of a person, especially:
* a change from human form to animal form and vice versa
* a change in appearance from one person to another
Although shapeshifting is not believed to be scientifically or medically possible, it is a common theme in myth and legend and a popular theme in science fiction and fantasy stories.
"Shapeshifting" often refers to characters who change form on their own, whether voluntarily or involuntarily, while "transformation" refers more commonly to externally imposed change of form, whether by magic or sufficiently advanced technology. However, there is no settled agreement on the terminology. Popular shapeshifting creatures in myths and legends are werewolves and vampires (mostly of European, Canadian, and Native American/early American origin), the kitsune or were-foxes of Japan, and the gods and goddesses of numerous mythologies, such as Loki from Norse mythology or Proteus from Greek mythology. It was also common for deities to transform mortals into animals and plants.
Although shapeshifting to the form of a wolf is specifically known as lycanthropy, and such creatures who undergo such change are called lycanthropes, those terms have also been used to describe any human-animal transformations and the creatures who undergo them. Therianthropy is the more general term for human-animal shifts, but it is rarely used in that capacity. Other terms for shapeshifters include metamorph, skin-walker, mimic, therianthrope, and were.
Almost every culture around the world has some type of shapeshifting myth, and almost every commonly found animal (and some not-so-common ones) probably have a shapeshifting myth attached to them. Usually, the animal involved in the transformation is most likely indigenous to or prevalent in the area from which the story derives.
Also, it is worthy to note that while the popular idea of a shapeshifter is of a human being who turns into something else, there are numerous myths about animals that can transform themselves as well.