What is the origin of the idiom "cock-and-bull story" and when to use it?

The idiom "cock-and-bull story" has its origins in the 17th century and refers to a fanciful, improbable, or exaggerated tale. The phrase likely comes from the names of two inns, the "Cock" and the "Bull," which were known for hosting travelers and entertaining them with extravagant and fictitious stories. Today, this expression is used to describe a narrative that is fabricated, unbelievable, or intended to deceive, often characterized by its lack of credibility.