Many Greek people recognized the 14 major gods and goddesses: Zeus, Hera, Poseidon, Apollo, Artemis,Aphrodite, Ares, Dionysus, Hephaestus, Athena, Hermes, Demeter, Hestia, Hades though philosophical religions such as Stoicism and forms of Platonism posited a transcendent single deity. Different cities worshipped different deities, sometimes with epithets that specified their local nature.
The Ancient greeks worshiped Zeus because they thought he was the most powerful and faithful god to them, and because they believed that he did the greatest accomplishments as a god.