Here is some information about understanding and interpreting this family tree of the Olympian gods and goddesses. Starting from the top, the first two names on this chart - Kronos and Rheia - represent the parents of the major gods of the Greek pantheon. The second row of names includes the deities of the first generation of important offspring. They are Zeus, Hestia, Hera, Demeter, Hades, and Poseidon. The second generation consists of Apollo, Artemis, Hephaistos, Ares, and Athena. While Persephone (who was the daughter of Demeter and Zeus), Hebe, and Eileithyia (both children of Zeus and Hera) are all significant goddesses, they are not usually categorized in the same class as their more illustrious siblings. Leto is the daughter of Coeus and Phoebe.
Astute students of Greek mythology will also notice that a trio of essential names is missing from this chart. Dionysos (the Greek god of wine, mysteries, and the theatre), Hermes (the Greek god of merchants), and Aphrodite (the Greek goddess of love and beauty) are all noticeably absent from the list. This was done in the interest of space and legibility, and the omission is not in any way meant to diminish the significance of these divine beings. It is worth noting that these three gods were all the children of Zeus: Dionysos was the son of Zeus and Semele, Hermes was the son of Zeus and Maia, and Aphrodite was considered by some sources to be the daughter of Zeus and Dione.