A werewolf is a mythological creature that is sometimes a person and sometimes a wolf, usually believed to prey on people. In different versions of folklore, the werewolf is either a magician or the object of a curse. In much modern literature and film, the werewolf is said to shape-shift under the influence of the full moon and to be vulnerable only to a silver bullet. The word werewolf derives from Old English wer-wulf, meaning "man-wolf."
Tales of werewolves abound in cultures from all over Europe, from Russia to England and from Norway to Italy. Werewolves appear in some of the earliest literature of these regions. Because the legend spans such a vast geographical and cultural area, there are many variations.
A person may become a werewolf in many different ways, according to different cultures. The curse may be effected by engaging in cannibalism or Satanism. Alternatively, stripping and wearing articles made of wolf skin, drinking water from a wolf's footprint, or being bitten by a werewolf may cause the change. A superstition arose in Portugal and later in Brazil that the seventh son, or the seventh son of a seventh son, would be born a werewolf. To this day, the President of Brazil is officially the godfather of all seventh sons, a practice resulting from the tendency in earlier times of parents to abandon such children.
Some versions of the werewolf tale claim that there are cures for the condition, while others hold that death by silver bullet is the only solution. One such cure is to remove the wolf skin, if wearing it brought about the condition. Other remedies include religious methods, such as reproaching the werewolf or making the sign of the cross. Magical cures include drawing three drops of blood and striking the creature with a knife three times on the head. Strangely, while most people no longer believe in werewolves, there is a medical condition known as clinical lycanthropy in which the sufferer believes himself or herself to be a werewolf.