This article is from the Greece FAQ, by Nikolaos (Nick) C. Fotis, email@example.com with numerous contributions by others.
It's rather easy to remember most of the 12 Gods of Greek Ancient
Mythology. The most easy to remember are:
Zeus, Hera, Athena, Poseidon, Aphrodite, Hephaestus, Ares, Apollo, Hermes,
The number 12 is the most troublesome:
> From: firstname.lastname@example.org (Richard Wallace)
> Newsgroups: soc.culture.greek
> Subject: Re: REQUEST: Greek Gods
The most usual list has Hestia as number twelve. She was the goddess of
hearth and home, and so a rather passive figure, and from time to time
people seem to have thought that she didn't really earn her place, and
put someone else in instead.
So far as I know, Hades is one of the twelve only in the list in Plato's
Phaedrus (and perhaps, by implication, in the Laws),
and there Plato makes it quite clear that HE has made the
decision to leave Hestia out. I think Hades does not figure in the
normal lists because they are the twelve OLYMPIAN gods, and Hades does
not normally come to Olympus (though Poseidon does).
Sometimes you get Dionysus instead of Hestia. He is a rather aberrant
god anyway (either because he was a late-comer to Greek religion or for
some other reason) - in any case he doesn't normally appear in the list.
There is some evidence that there was a local tradition at Olympia which
substituted Kronos, Rhea, and Alpheios (the local river god) for
Hephaistos, Demeter, and Hestia, and there are other cases of the
insertion of local gods into the list in particular localities,
presumably out of local patriotism.
Mostly, they referred to them simply as 'the twelve', no doubt leaving
it open to each individual to write in his own list!
[ Personally, I feel that Dionysus was mentioned most often in the
mainland Greece mythology, at least in Attica -- nfotis ]
THE MAIN GODS AND GODDESSES OF THE ANCIENT GREEK RELIGION
Greek Latin meaning Name Name --------- ------ Zeus Zeus, Jupiter Master of the sky, father of the gods and men. Hera Juno Wife of Zeus, protector of marriage Poseidon Neptune Brother of Zeus, god of the sea Athena Minerva Goddess of wisdom, protector of arts and crafts Apollo Apollo God of the sun and music Artemis Diana Apollo's sister, goddess of hunting Aphrodite Venus Goddess of beauty and love Hephaestus Vulcan God of fire, protector of metal workers Ares Mars God of war Hermes Mercury Messenger of gods and god of trade Demeter Ceres Goddess of agriculture Persephone, Kore Proserpina Demeter's daughter, queen of the Underworld (Hades) Pluton, Ades Pluton King of the Underworld Dionysus, Bacchos Bacchus God of wine, vegetation and fertility Asklepios Aesculapius God of medicine