Cronus: Cronus was the ruling Titan who came to power by castrating his Father Uranus. His wife was Rhea. There offspring were the first of the Olympians. To insure his safety Cronus ate each of the children as they were born. This worked until Rhea, unhappy at the loss of her children, tricked Cronus into swallowing a rock, instead of Zeus. When he grew up Zeus would revolt against Cronus and the other Titans, defeat them, and banish them to Tartarus in the underworld. But Cronus managed to escape to Italy, where he ruled as Saturn.
Gaea: Gaea is the Earth goddess. She mated with her son Uranus to produce the remaining Titans. Gaea seems to have started as a neolithic earth-mother worshipped before the Indo-European invasion that eventually lead to the Hellinistic civilization.
Uranus: Uranus is the sky god and first ruler. He is the son of Gaea, who created him without help. He then became the husband of Gaea and together they had many offspring, including twelve of the Titans.
Rhea: Rhea was the wife of Cronus. Cronus made it a practice to swallow their children. To avoid this, Rhea tricked Cronus into swallowing a rock, saving her son Zeus.
Oceanus: Oceanus is the unending stream of water encircling the world. Together with his wife Tethys produced the rivers and the three thousand ocean nymphs.
Tethys: Tethys is the wife of Oceanus. Together they produced the rivers and the three thousand ocean nymphs.
Hyperion: Hyperion is the Titan of light, the father of the sun, the moon, and the dawn.
Mnemosyne: Mnemosyne was the Titan of memory and the mother of Muses.
Thea: The wife of her brother Hyperion, Thea gave birth to Helios, Eos, and Selene. She is the goddess from whom light emanates and considered especially beautiful.
Atlas: Atlas was the son of Iapetus. Unlike his brothers Prometheus and Epimetheus, Atlas fought with the other Titans supporting Cronus against Zeus. Due to Cronus’s advance age Atlas lead the Titan’s in battle. As a result he was singled out by Zeus for a special punishment and made to hold up the world on his back.
Prometheus: His name means "forethought" and he was able to foretell the future. He was the son of Iapetus. When Zeus revolted against Cronus Prometheus deserted the other Titans and fought on Zeus side.
Iapetus: Iapetus was the father of Prometheus, Epimetheus, and Atlas.
There were twelve Olympian Gods who ruled the earth after the Titans had been overthrown. They resided atop of Mount Olympus. They were Zeus, Ares, Athena, Apollo, Hera, Poseidon, Hades, Hestia, Hermes, Aphrodite, Artemis, and Hephaestus.
Zeus: Zeus was the god of the sky and ruler of the Olympian gods. Zeus overthew his Father Cronus. He then drew lots with his brothers Poseidon and Hades. Zeus won the draw and became the supreme ruler of the gods. He is lord of the sky, the rain god. His weapon is a thunderbolt which he hurls at those who displease him.
Ares: Ares was the son of Zeus and Hera. God of war, frenzy, hatred, and bloodshed.
Athena: Athena is the Greek virgin goddess of reason, intelligent activity, arts and literature. Athena is the daughter of Zeus. She sprang full grown in armour from his forehead, thus has no mother. She is fierce and brave in battle but, only wars to defend the state and home from outside enemies.
Apollo: Apollo is the son of Zeus and Leto. His twin sister is Artemis. He is the god of music, playing a golden lyre. The Archer, far shooting with a silver bow. The god of healing who taught man medicine. The god of light. The god of truth, who can not speak a lie.
Hera: Hera is Zeus wife and sister. She was raised by the Titans Ocean and Tethys. She is the supreme goddess, goddess of marriage and childbirth and takes special care of married women.
Poseidon: God of the sea, protector of all waters. Poseidon is the brother of Zeus. After the overthow of their Father Cronus he drew lots with Zeus and Hades, another brother, for shares of the world. His prize was to become lord of the sea. He was widely worshiped by seamen.
Hermes: Hermes is the son of Zeus and Maia. He is Zeus messenger. He is the fastest of the gods. He wears winged sandals, a winged hat, and carries a magic wand. He is the god of commerce. He is the guide for the dead to go to the underworld.
Hades/Pluto: Hades is the brother of Zeus. After the overthow of their Father Cronus he drew lots with Zeus and Poseidon, another brother, for shares of the world. He had the worst draw and was made lord of the underworld, ruling over the dead.
Hestia: Hestia is Zeus sister. She is a virgin goddess. She does not have a distinct personality. She is the Goddess of the Hearth, the symbol of the house around which a new born child is carried before it is received into the family. Each city had a public hearth sacred to Hestia, where the fire was never allowed to go out. Of all the Olympians, she is the mildest, most upright and most charitable.
Aphrodite: Aphrodite is the goddess of love, desire and beauty. In addition to her natural gifts she has a magical girdle that compels anyone she wishes to desire her.
Artemis: She was goddess of chastity, virginity, the hunt, the moon, and the natural environment. Artemis is the daughter of Zeus and Leto. Her twin brother is Apollo.
Hephaestus: Hephaestus is the son of Zeus and Hera. Sometimes it is said that Hera alone produced him and that he has no father. He is the only god to be physically ugly. He is also lame. He is the patron god of both smiths and weavers. He is kind and peace loving. His wife is Aphrodite.