One of the considerations a mystery writer must make is how many red herrings to utilize and how to use them effectively. While there is no secret formula, conventional belief is that one or two is sufficient. When done well, they provide intricacy to narratives and fascination to stories. When used excessively, they can become annoying and detract from more important aspects of fiction. The earliest references to red herrings in literature appear in English crime novels written by Charles Dickens between 1859 and 1866. The term was originally coined by his friend and collaborator Henry Fielding to describe parts of narrative stories that seemingly serve no purpose other than to mislead the reader. Dickens popularized the usage of the term "red herring" in English. Prior to this time, writers used various terms to describe characters or events that were not relevant to the story but that distracted from it. Some of these terms include: distraction, obstacle, impediment, anomaly, exception, et cetera. Red herrings are commonly used in modern literature and journalism. In crime fiction, a red herring is often a clue that appears to point to one suspect while actually pointing to another. This allows the author to explain what happened that night without revealing the actual killer's identity. Red herrings are also used to increase intrigue and suspense.