Despite its name, a typical urban legend does not necessarily originate in an urban setting. The term is simply used to differentiate modern legend from traditional folklore in preindustrial times. For this reason, sociologists and folklorists prefer the term "contemporary legend."
Urban legends are sometimes repeated in news stories and, in recent years, distributed by e-mail. People frequently allege that such tales happened to a "friend of a friend"—so often, in fact, that "friend of a friend," ("FOAF") has become a commonly used term when recounting this type of story.
Some urban legends have passed through the years with only minor changes to suit regional variations. One example is the story of a woman killed by spiders nesting in her elaborate hairdo. More recent legends tend to reflect modern circumstances, like the story of people ambushed, anesthetized, and waking up minus one kidney, which was surgically removed for transplantation.
The first study of the concept now described as an "urban legend" seems to be Edgar Morin's La Rumeur d'Orléans (in French) in 1969. Jan Harold Brunvand, professor of English at the University of Utah, used the term "urban legend" in print as early as 1979 in a book review appearing in the Journal of American Folklore 92:362. Even at that time, researchers had been writing about the phenomenon for a long time, but with varying terminology.
Brunvand used his collection of legends, The Vanishing Hitchhiker: American Urban Legends & Their Meanings, to make two points: first, that legends and folklore do not occur exclusively in so-called primitive or traditional societies, and second, that one could learn much about urban and modern culture by studying such tales. Brunvand has since published a series of similar books, and is credited as the first to use the term vector (inspired by the concept of biological vectors) to describe a person or entity passing on an urban legend.
The compelling appeal of a typical urban legend is its elements of mystery, horror, fear or humor. Many urban legends are presented as warnings or cautionary tales, while others might be more aptly called "widely dispersed misinformation," such as the erroneous belief that a college student will automatically pass all courses in a semester if one's roommate commits suicide. While such "facts" may not have the narrative elements of traditional urban legend, they are nevertheless conveyed from person to person with the typical elements of horror, humor or caution.
Much like some folktales of old, there are urban legends dealing with unexplained phenomena such as phantom apparitions.
The teller of an urban legend may claim it happened to a friend, which serves to personalize and enhance the power of the narrative. Since people, unconsciously or otherwise, often exaggerate, conflate or edit stories when telling them, urban legends can evolve over time.
Many urban legends depict horrific crimes, contaminated foods or other situations which would affect many people. Anyone believing such stories might feel compelled to warn loved ones.
Many urban legends are essentially extended jokes, told as if they were true events. Others, like tall tales in general, contain a grain of truth. The urban legend that Coca-Cola developed the drink Fanta to sell in Nazi Germany without public backlash originated as the actual tale of German Max Keith, who invented the drink and ran Coca-Cola's operations in Nazi Germany during World War II.
Some urban legends are morality tales that depict someone, usually a child, acting in a disagreeable manner, only to wind up in trouble, hurt, or dead.
With the advent of the internet, a new kind of urban legend is beginning to emerge where a passage from a book, television show, film or play is taken wholesale and attributed to some well-known social or political figure, largely through chain e-mails.
Regardless of origins, urban legends typically include one or more common elements: the legend is retold on behalf of the original witness or participant; dire warnings are often given for those who might not heed the advice or lesson contained therein (this is a typical element of many e-mail phishing scams); and it is often touted as "something a friend told me," while the friend is identified by first name only or not identified at all One of the classic hallmarks of false urban legends is a total lack of specific information regarding the incident e.g. names, dates, locations, when or where it was published, or similar information.
Additionally, urban legends will often contain a grain of truth, in that even if an urban legend is highly improbable or implausible, most are at least possible e.g. a serial killer deliberately hiding in the back seat of a car.
For this reason, it is characteristic of groups within which a given narrative circulates to react very negatively to claims or demonstrations of non-factuality; an example would be the expressions of outrage by police officers who are told that adulteration of Halloween treats by strangers is extremely rare, if it has occurred at all. or the vehement responses of Vietnam veterans to the Jerry Lembke’s 1998 study ("The Spitting Image: Myth, Media and the Legacy of Viet Nam") of 495 news articles on returning veterans that showed only 32 incidents of any type of animosity or antagonism towards veterans, and that the only reported incidents of spitting were directed by supporters of veterans, at protestors. However, the narrative contains a truth for its tellers which is distinct from historical factuality: “The persistence of spat-upon Vietnam veteran stories suggests that they continue to fill a need in American culture. The image of spat-upon veterans is the icon through which many people remember the loss of the war, the centerpiece of a betrayal narrative that understands the war to have been lost because of treason on the home front.” Newspaper columnist Bob Greene received numerous responses to his solicitation of stories from veterans who claimed to have been spit upon (though none, even from anonymous sources, claiming to have done any spitting).
The term urban myth is preferred in some languages such as Mexican Spanish, where conventional coinage is "mito urbano" rather than "leyenda urbana." In French, urban legends are usually called rumeurs d'Orléans ("Orleans rumours") after Edgar Morin's work. "Légende contemporaine" is an acceptable translation of the English idiom, instead of "légende urbaine", which is an improper and meaningless verbatim translation, though used by some French sociologists or journalists. But neither expression is commonly used: for ordinary French people, the more genuine terms rumeur or canular (hoax), not to mention more colloquial and expressive words, describe this phenomenon of "viral spread tall story" properly enough.
Some scholars prefer the term contemporary legend to highlight those tales that originated relatively recently. This is, of course, true for all periods in history; for instance, an eighteenth-century pamphlet alleging that a woman was tricked into eating the ashes of her lover's heart would be a contemporary legend with respect to the eighteenth century.
The main scholarly association on the subject is called The International Society for Contemporary Legend Research; its journal is titled Contemporary Legend.
The United States Department of Energy has a service called Hoaxbusters that deals with all sorts of computer-distributed hoaxes and legends.
Television shows such as Urban Legends, Beyond Belief: Fact or Fiction, and later Mostly True Stories: Urban Legends Revealed feature re-enactments of urban legends detailing the accounts of the tales and (typically) later in the show, these programs reveal any factual basis they may have.