A
healing factor is the ability of some characters in
fiction to recover from bodily
injuries or disease at a
superhuman rate. Since the introduction of
Wolverine by
Marvel Comics in 1974 and inspired by the immense popularity of the character, superhuman healing has become a fairly common power featured in
comic books,
novels,
television,
film, and other mediums. The overall efficiency of a character's healing factor often fluctuates due to various writers applying a very broad degree of
artistic license. As a result, especially concerning characters depicted in comic books, it has become a very common source of debate among fans. Over the years, it has also become common for healing factors to have an umbrella effect in which it serves as a partial source for multiple superhuman abilities; with varying degrees and numbers of powers with superhuman strength, speed, stamina, agility, reflexes, durability and/or senses as the most common. The source of a character's healing factor, depending upon the medium, usually ranges from natural genetic mutation, accidental exposure to radioactive materials, artificially induced genetic enhancement, cybernetic augmentation, magic or even a combination of different factors.