bring a knife to a gunfight

What is the origin of the idiom "bring a knife to a gunfight" and when to use it?

The idiom "bring a knife to a gunfight" originated in the American West during the late 19th century, a time when gunfights were a common occurrence. It was a time when people carried guns for protection and disputes were often settled with a duel. Today, the idiom is used in a more figurative sense to describe any situation where someone is ill-equipped or unprepared to deal with a difficult challenge or task.