Gods and Goddesses
Ancient Greeks believed in multiple gods/goddesses, making them polytheistic. There were tons of gods and goddesses that the Greeks worshipped, but the main ones were the Olympians. The 12 Olympian gods and goddesses are Athena, Artemis, Apollo, Ares, Aphrodite, Hephaestus, Hermes, Poseidon, Demeter, Hera, Zeus, Hestia, and Dionysus. There are only 12 of them, but 13 were listed because sometimes Hestia is the 13th, and other times it's Dionysus. The Olympians lived on Mt. Olympus. Zeus is said to be the king of the gods, with Hera as his wife. Another largely recognized deity is Hades, who ruled the underworld with his wife, Persephone. Many of these gods and goddesses are still very known today, but they aren't exactly worshipped anymore.
Zeus, the king of the Greek gods.
Ancient Greek Worshipping
Dionysia, an ancient Greek festival that's dedicated to the wine god, Dionysus.
The Ancient Greeks worshipped the gods in many ways. Many houses had an altar to Hestia, the goddess of the hearth, and they would also sacrifice a portion of their meal to her every day. There were many other forms of sacrifices too, some of them which are more extreme than others, like sacrificing animals. They also created large temples dedicated to a god or goddess. One of the most famous ones is the Parthenon, built in Athens and dedicated to Athena, the goddess of wisdom. Many festivals were celebrated in honor of the gods, the most famous being the Olympics, which was dedicated to Zeus. Some other festivals include Lykaia, which was celebrated in Arcadia for the god Pan, and Dionysia, which was held in Athens and dedicated to Dionysus. Nowadays, gods and goddesses aren't worshipped in similar ways anymore.