What is the origin of the idiom "silver bullet" and when to use it?

The idiom "silver bullet" originates from folklore and popular culture, particularly the belief that a silver bullet is the only way to kill a werewolf or other supernatural creatures in some myths. In its figurative usage, a "silver bullet" refers to a simple and magical solution that can effectively solve a complex problem or issue. It signifies a single, direct, and highly effective method or action to achieve a desired outcome.