What is the difference between a myth and a legend?

In the academic fields of mythology, mythography, or folkloristics, a myth (mythos) is a sacred story concerning the origins of the world or how the world and the creatures in it came to have their present form. The active beings in myths are generally gods and heroes. Myths often are said to take place before recorded history begins. In saying that a myth is a sacred narrative, what is meant is that a myth is believed to be true by people who attach religious or spiritual significance to it. Use of the term by scholars does not imply that the narrative is either true or false. See also legend and tale.
A myth in popular use is something that is widely believed to be false. This usage, which is often pejorative, arose from labeling the religious myths and beliefs of other cultures as being incorrect, but it has spread to cover non-religious beliefs as well. Because of this usage, many people take offense when the religious narratives they believe to be true are called myths (see Religion and mythology for more information). This usage is frequently confused with fiction, legend, fairy tale, folklore, fable, and urban legend, each of which has a distinct meaning in academia.
Urban myth is an alternate (not academic) term for urban legend

http://en.wikipedia.org/wiki/Myths

Many urban legends are framed as complete stories, with plot and characters. Urban legends often resemble a proper joke, especially in the manner of transmission, but are much darker in tone and theme.
The compelling appeal of a typical urban legend are 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.[1] 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 folk tales of old, there are urban legends dealing with unexplained phenomena such as phantom apparitions.

Many urban legends depict horrific crimes, contaminated foods or other situations which, if true, might affect a lot of people. Anyone believing such stories might feel compelled to warn loved ones.
A person might also pass on non cautionary information simply because it is funny or interesting. Many urban legends are essentially extended jokes, told as if they were true events. In some cases they may have originated as pure jokes, personalized by a subsequent teller to add point and force. http://en.wikipedia.org/wiki/Urban_legend


Myths are traditional stories occurring in a timeless past. They involve supernatural elements and are beyond the frontiers of logic. Long ago, when our ancestors heard the sound of thunder and saw lightening, they were frightened because they could not understand why these things happened. In order to understand these and other natural events, they created stories. The stories were handed down from generation to generation all around the world. Although myths are not based on objective truth, they reflect both universal worries and the worries of specific cultures. On the other hand, legends, however, are stories about real people who are famous for doing something brave or extraordinary. Every time the story was told, it became more exaggerated and so it is now difficult to tell how much of the story is really true. One myth shared by Domicans and Puerto Ricans is that of a ghost called cuco. Ususally children are told to scare them into behaving. The coqui is a Puerto Rican legend which has been spread in many parts of the world. Coqui are real, similar to frogs. Many have blamed the coqui for dead sheep and other strange deaths which has not beeen proven to be true but stories are exaggerated as imes goes on.