one of the principal Hindu deities. Vishnu combines many lesser divine figures and local heroes, chiefly through his avatars, particularly Rama and Krishna. His appearances are innumerable; he is often said to have 10 avatars, but not always the same 10. Among the 1,000 names of Vishnu (repeated as an act of devotion by his worshippers) are Vasudeva, Narayana, and Hari.

Vishnu was not a major deity in the Vedic period. A few Rigvedic hymns (c. 1400–1000 BCE) associate him with the Sun, and one hymn relates the legend of his three strides across the universe, which formed the basis of the myth of his avatar Vamana (Vāmana), the dwarf. Legends of figures that later became other avatars, such as the fish that saves humankind from a great flood, are also found in the early literature. By the time of the Mahabharata (the great Sanskrit epic that appeared in its final form about 400 CE), the avatars began to be identified with Vishnu. Vishnu is said to manifest a portion of himself anytime he is needed to fight evil and to protect dharma (moral and religious law). Not all avatars are wholly benevolent; some, such as Parashurama and Krishna, bring about the death of many innocent people, and the Buddha corrupts the pious antigods. Vishnu's vahana, his vehicle in the world, is the bird Garuda (Garuḍa); his heaven is called Vaikuntha.