The scope of Greek mythology is enormous. It extends from the horrific crimes of the early gods and the bloody wars of Troy and Thebes, to the childhood pranks of Hermes and the touching grief of Demeter for Persephone. The legions of gods, goddesses, heroes, heroines, monsters, daemons, nymphs, satyrs, and centaurs that one encounters in traversing this vast landscape are beyond count.
Greek mythology has an approximate internal chronology. While contradictions in the material make an absolute timeline impossible, it breaks down roughly into:
-an age of gods,
-an age when men and gods mingled freely, and
-an age of heroes where divine activity was more limited.
While the myths of the age of gods have often been more interesting to contemporary students of myth, Greek authors of the archaic and classical eras had a clear preference for those of the age of heroes: the heroic Iliad and Odyssey, for example, dwarfed the divine-focused Theogony and Homeric Hymns in both size and popularity.
http://en.wikipedia.org/wiki/Greek_mythology