A solar deity (also sun god or sun goddess) is a sky deity who represents the Sun, or an aspect of it, usually by its perceived power and strength. Solar deities and sun worship can be found throughout most of recorded history in various forms. The Sun is sometimes referred to by its Latin name Sol or by its Greek name Helios. The English word sun stems from Proto-Germanic *sunnǭ.
The Neolithic concept of a "solar barge" (also "solar bark", "solar barque", "solar boat" and "sun boat", a mythological representation of the sun riding in a boat) is found in the later myths of ancient Egypt, with Ra and Horus. Predynasty Egyptian beliefs attribute Atum as the sun-god and Horus as a god of the sky and sun. As the Old Kingdom theocracy gained power, early beliefs were incorporated with the expanding popularity of Ra and the Osiris-Horus mythology. Atum became Ra-Atum, the rays of the setting sun. Osiris became the divine heir to Atum's power on Earth and passes his divine authority to his son Horus. Early Egyptian myths imply the sun is within the lioness, Sekhmet, at night and is reflected in her eyes; or that it is within the cow, Hathor, during the night, being reborn each morning as her son (bull).
Mesopotamian Shamash plays an important role during the Bronze Age, and "my Sun" is eventually used as an address to royalty. Similarly, South American cultures have a tradition of Sun worship, as with the Incan Inti.
Proto-Indo-European religion has a solar chariot, the sun as traversing the sky in a chariot. In Germanic mythology this is Sol, in Vedic Surya, and in Greek Helios (occasionally referred to as Titan) and (sometimes) as Apollo. In Proto-indo-european mythology the sun appears to be a multilayered figure, manifested as a goddess but also perceived as the eye of the sky father Dyeus.