In Greek mythology, Hephaestus (also known as Hephaistos and several other spellings) is the god of blacksmiths and craftsmen. Hephaestus was the son of Zeus and Hera.
The name Hephaestus probably has its origin in the name of places prior the settlement of what we now know as Ancient Greek civilization.
The pronunciation of Hephaestus in English can vary between British and American English. The only variation is how the "ae" is pronounced. Usually in the US, Hephaestus is pronounced as Heh-fehs-tus, with an "eh" sound standing for the "ae", as heard in the first part of the audio pronunciation. In the UK, Hephaestus is usually pronounced as Heh-fee-stus, with the "ae" pronounced with an "ee" sound, as heard in the second part of the audio pronunciation.