For millennia, people considered dragons to be real, and the vivid lore of dragons has touched societies from Central America to Europe, and from Egypt to China. The popularity of dragons can easily be assessed by the number of motion pictures that include them as an integral part of their narrative, from the friendly dragons of children's cartoons to the monsters being bred underground to unleash their horrors on humanity. Indeed, some of humanity's deepest cultural myths have included dragons, from the Greek and Georgian tale of Jason and the Argonauts to the stories from ancient China that influence modern New Year's festivities.

The English word "dragon" comes from the Greek word "drakon," which means "snake," and while people today may have a hard time imagining a dragon as a simple snake, some scientists think that the international nature of the myth is based on the presence of snakes on nearly every continent. Oxford professor of medieval European literature Carolyne Larrington explained, "The anthropologist David E. Jones has suggested that the dragon myth takes its origins from an innate fear of snakes, genetically encoded in humans from the time of our earliest differentiation from other primates. It is true, of course, that it makes evolutionary sense to avoid dangerous animals of every kind, but it is less clear why people should invent stories about imaginary oversized serpents in particular. Nevertheless, there is a clear benefit to tales that warn children against straying into perilous marshy areas where the serpent might seize them, or against scrambling up treacherous mountain sides in search of monsters and treasure hoards."

Nonetheless, some people feel that there must be more to this idea of dragons than the mere shape and danger of a snake, because so many of the myths include details that go beyond the simple behavior of class Reptilia, order Squamata, and suborder Serpentes. Close to 30 families of snakes are recognized in modern taxonomy, including 520 genera and more than 4,000 species. As many know, most are harmless, but plenty of snakes possess deadly venom.
Though dragons are often depicted as fearsome and malevolent, not every culture viewed snakes in such a negative light. Some groups regarded snakes, and dragons, far more positively, like the Hopi natives of the American Southwest who believed that snakes were related to fertility, healing and positive transformation (Roderick and Davidson, 1988). The caduceus, a staff framed by two intertwining snakes, is still the symbol of medicine and the medical arts. Originally, it was the symbol related to the Greek god Hermes, messenger of the Olympian gods and protector of merchants, orators, thieves, travelers, and heralds.

As this suggests, even if most people are vaguely familiar with European dragons or Chinese dragons, these mythical creatures have featured in mythology and legends in dozens of nations around the world, from North America and Polynesia to Africa and India. Roughly three dozen named dragons have been documented in Europe, from Albania and Greece to France and Spain, and from Russia and Poland to Lithuania.

Dragons: The History of Dragon Legends and Folk Tales around the World