Hephaestus (; eight spellings; Greek: Ἥφαιστος, translit. Hḗphaistos) is the Greek god of blacksmiths, metalworking, carpenters, craftsmen, artisans, sculptors, metallurgy, fire (compare, however, with Hestia), and volcanoes. Hephaestus's Roman counterpart is Vulcan. In Greek mythology, Hephaestus was either the son of Zeus and Hera or he was Hera's parthenogenous child. He was cast off Mount Olympus by his mother Hera because of his lameness, the result of a congenital impairment; or in another account, by Zeus for protecting Hera from his advances (in which case his lameness would have been the result of his fall rather than the reason for it).

As a smithing god, Hephaestus made all the weapons of the gods in Olympus. He served as the blacksmith of the gods, and was worshipped in the manufacturing and industrial centres of Greece, particularly Athens. The cult of Hephaestus was based in Lemnos. Hephaestus's symbols are a smith's hammer, anvil, and a pair of tongs.