Greek mythology is a body of stories and teachings that belong to the ancient Greeks, concerning their gods and heroes, the nature of the world, and the origins and significance of their own cult and ritual practices. They were a part of religion in ancient Greece and are part of religion in modern Hellenism.

The main sources for our current knowledge of Greek mythology are the epic poems of Homer: the “Iliad” and the “Odyssey”, and the works of Hesiod: the “Theogony” and the “Works and Days”. Other poets completed the “epic cycle”, but these later and lesser poems now are lost almost entirely.

The Greek myths were initially propagated in an oral-poetic tradition most likely by Minoan and Mycenaean singers starting in the 18th century BC; eventually the myths of the heroes of the Trojan War and its aftermath became part of the mythical tradition about the city of Rome.

These myths are diverse in their themes, ranging from the creation of the world and the lives of deities, to more human issues such as love, betrayal, and revenge. Major characters include the gods Zeus, Poseidon, and Hades, the goddesses Hera, Demeter, and Athena, and heroes such as Hercules, Perseus, Theseus, and the warriors of the Trojan War like Achilles and Odysseus.

Greek mythology has had a profound influence on the culture, arts and literature of Western civilization and remains part of Western heritage and language. It has been a part of the educational fabric of many schools and universities, and has been frequently referenced in a variety of media.