A myth is a sacred narrative usually explaining how the world or humankind came to be in its present form, although, in a very broad sense, the word can refer to any traditional story. Myths typically involve supernatural characters and are endorsed by rulers or priests. They may arise as over-elaborated accounts of historical events, as allegory for or personification of natural phenomena, or as an explanation of ritual. They are transmitted to convey religious or idealized experience, to establish behavioral models, and to teach.

Source: WikiPedia