Apollo (Attic, Ionic, and Homeric Greek: Ἀπόλλων, Apollōn (gen.: Ἀπόλλωνος); Doric:Ἀπέλλων, Apellōn; Arcadocypriot: Ἀπείλων, Apeilōn; Aeolic: Ἄπλουν, Aploun; Latin:Apollō) is one of the most important and complex of the Olympian deities in classical Greek and Roman religion and Greek and Roman mythology. The ideal of the kouros (a beardless, athletic youth), Apollo has been variously recognized as a god of light and the sun, truth and prophecy, healing, plague, music, poetry, and more. Apollo is the son ofZeus and Leto, and has a twin sister, the chaste huntress Artemis. Apollo is known in Greek-influenced Etruscan mythology as Apulu.
As the patron of Delphi (Pythian Apollo), Apollo was an oracular god—the prophetic deity of the Delphic Oracle. Medicine and healing are associated with Apollo, whether through the god himself or mediated through his son Asclepius, yet Apollo was also seen as a god who could bring ill-health and deadly plague. Amongst the god's custodial charges, Apollo became associated with dominion over colonists, and as the patron defender of herds and flocks. As the leader of the Muses (Apollon Musegetes) and director of their choir, Apollo functioned as the patron god of music and poetry. Hermes created the lyre for him, and the instrument became a common attribute of Apollo. Hymns sung to Apollo were called paeans.
In Hellenistic times, especially during the 3rd century BCE, as Apollo Helios he became identified among Greeks with Helios, Titan god of the sun, and his sister Artemis similarly equated with Selene, Titan goddess of the moon. In Latin texts, on the other hand,Joseph Fontenrose declared himself unable to find any conflation of Apollo with Sol among the Augustan poets of the 1st century, not even in the conjurations of Aeneas and Latinusin Aeneid XII (161–215). Apollo and Helios/Sol remained separate beings in literary and mythological texts until the 3rd century CE.
The cult centers of Apollo in Greece, Delphi and Delos, date from the 8th century BCE. The Delos sanctuary was primarily dedicated to Artemis, Apollo's twin sister. At Delphi, Apollo was venerated as the slayer of Pytho. For the Greeks, Apollo was all the Gods in one and through the centuries he acquired different functions which could originate from different gods. In archaic Greece he was the prophet, the oracular god who in older times was connected with "healing". In classical Greece he was the god of light and of music, but in popular religion he had a strong function to keep away evil. Walter Burkert discerned three components in the prehistory of Apollo worship, which he termed "a Dorian-northwest Greek component, a Cretan-Minoan component, and a Syro-Hittite component."
From his eastern-origin Apollo brought the art of inspection from "symbols and omina" (σημεία και τέρατα : semeia kai terata), and of the observation of the omens of the days. The inspiration oracular-cult was probably introduced from Anatolia. The ritualismbelonged to Apollo from the beginning. The Greeks created the legalism, the supervision of the orders of the gods, and the demand for moderation and harmony. Apollo became the god of shining youth, the protector of music, spiritual-life, moderation and perceptible order. The improvement of the old Anatolian god, and his elevation to an intellectual sphere, may be considered an achievement of the Greekpeople.