Most people remember the moment when, as children, they first heard about Count Dracula. The chill of pure fear seems always to have been followed by an awful certainty - as if we had always known the truth of the story, as if Dracula had been lurking out there with the wolves all the time, just outside our field of vision. Hearing the tale from another person simply puts flesh on the bones of an instinctive horror.

The vampire myth tends to be dealt with in a cursory fashion by most textbooks on mythology, probably because it is not part of a discrete belief-system. Yet its enduring popularity five centuries after the death of Vlad the Impaler and 100 years since the publication of Bram Stoker’s novel demonstrates how it taps directly into something deep in the human psyche.

The vampire also shows us that a myth is more than simply a story or folktale.

A good myth should include some of the grand themes that have always obsessed human beings: death, corruption; the possibility of immortality and the terrible price that must paid for it; evil and the loneliness of the eternal Outsider.

The other element by which a myth stands the test of time is the Grain of Historical Truth factor. In Dracula’s case, Vlad V, “the Impaler”, was a real 15th-century Romanian prince who devised novel ways of disposing of his enemies. Castle Dracula is a real castle, while Countess Elisabeth Bathory of Hungary patented the use of murdered virgins’ blood as anti-wrinkle cream. The vampire bat is also a fresh-and-blood creature that lives in South America. All this is enough to plant a seed of doubt in any rational mind come midnight.

But if myths end up as metaphorical illustrations of our deepest hopes and fears, they often start life as attempts to explain how things came to be.

Creation myths seem to be common to all cultures, and are often remarkably similar - this is where myth meets religion. Interestingly, it is quite possible to argue that all religion is myth, but not that all myths are religious, as myths exist beyond religion.

Modern, post-Darwinian Christians tend to insist, a little sheepishly, that the story of God’s creation of the world in six days, and the temptation and Fall of Adam and Eve were never intended to be taken literally, that they are poetic allegories illustrating a deeper truth. But they are still taken literally by fundamentalists. On the other side of the world, the Australian aboriginal Dreamtime is both a lost era when creator spirits walked the earth, and a contemporary parallel world of the spirits.

The ancient Greeks saw creation arising out of conflict, when the Titan Cronos (time) released his mother, Earth (Gaia), from the oppressive embrace of his father, the sky (Uranus). Cronos married Rhea, and started eating his own children to prevent them usurping his authority. Zeus, however, escaped and founded a vast, quarrelsome, and petulant family of gods on Mount of Olympus, each one with a different sphere of influence. The theme of continual conflict between the forces of good and evil is another of the enduring themes of myth and religion.

The Greek version of creation derived from much earlier ones in Mesopotomia (from around 3000BC), while in India, several creation myths coexist, as told in the hymns of the Rig Veda (from about 1500BC). In one version, the sky god commits incest with his daughter, the dawn, spilling his seed on the ground.

The seed of the god is the origin of the the universe.

Stories of great floods also seem common to most cultures, perhaps not surprising when you consider that early civilisations developed along river valleys. The story of Noah familiar to Christians was anticipated by a remarkably similar story told in ancient Mesopotamia, some 2000 years before the civilisation of ancient Greece. The Incas of Peru had their own Noah story in which a man and a woman survive by floating in a box, while in an Indian myth, Manu is warned of a deluge by a fish, builds a boat, lands on one of the Himalayan peaks and goes on to father mankind via an incestuous union with his daughter.

Because early civilisation was agricultural and lives were at the mercy of nature and the elements, the other great mythological and religious themes common to all humanity is that of resurrection, rebirth and fertility. These themes are personified by Egyptians as Isis, by the Greeks as Demeter and the Scandinavians as Freya or Frigga. They are transformed into metaphor and ritual by Christians, Celts, Aztecs and Africans.

While explanatory myths and fertility rites from the past are fascinating for historians, the myths that still strike a chord of recognition in an urban, post industrial, computerised age are those that tap into the constants of human experience. The oldest myth we know about is the story of Gilgamesh, a warrior king of Sumer of Mesopotamia. Part mortal, part divine, (like so many later heroes such as Hercules and King Arthur), he tries like so many after him to obtain immortality. So from the “cradle of civilisation” comes the yearning for everlasting life. There may be 2000 years from Gilgamesh to the Iliad, but Achilles is one of his spiritual descendants.

Greek and Roman mythology still lives and breathes in the late 20th century because it permeates modern European languages via their Greek and Latin roots.

English speakers talking about chronology, chronicles or synchronicity are all calling up the spirit of the Titan lord of Time who castrated his sky father and tried to devour his children. People talking about Achilles’ heels probably do so without thinking of the warrior whose incomplete bath in the river Styx led to his doom.

Sisyphus still has a place in the heart of anyone who has ever had a routine job - he was punished for trickery by being condemned to push a marble boulder up a mountain, only to see it roll down again for eternity. Narcissus, the beautiful young man who fell in love with his own reflection, is a familiar type today, and has also been immortalised in the language, as have Tantalus, the chimera, Hercules, Nemesis and others. The sirens, however, have been transformed from the fatal seducers of myth into mechanical warnings of danger.

Even the planets of the solar system are named after Roman deities, while our weekdays derive from Norse gods.

Earlier this century, Sigmund Freud found in the story of Oedipus, who inadvertently married his mother and killed his father, the prototype of a psychological conflict in all infant boys, while Karl Jung believed that mythical figures, or archetypes, were the product of a collective unconscious.

As the more potent of the old myths are re-worked to serve new purposes, new myths are emerging of alien abductions, UFOs, millennial catastrophe, or technological apocalypse. Meanwhile the old myths are preserved in their pure form in painting, sculpture, poetry and song.