Myths, as compared with folk tales, are usually in a special category of seriousness: they are believed to have "really happened,"or to have some exceptional significance in explaining certain features of life, such as ritual. Again, whereas folk tales simply interchange motifs and develop variants, myths show an odd tendency to stick together and build up bigger structures. We have creation myths, fall and flood myths, metamorphose and dying-god myths. - Northrop Frye