Vishnu (Sanskrit ?????? Vi??u) is the Supreme god in the Vaishnavite tradition of Hinduism. Smarta followers of Adi Shankara; among others; venerate Vishnu as one of the five primary forms of God.

The Vishnu Sahasranama declares Vishnu as Paramatma (supreme soul) and Parameshwara (supreme God). It describes Vishnu as the All-Pervading essence of all beings; the master of - and beyond - the past; present and future; one who supports; sustains and governs the Universe and originates and develops all elements within. Vishnu governs the aspect of preservation and sustenance of the universe; so he is called 'Preserver of the Universe'.

In the Puranas; Vishnu is described as having the divine colour of water filled clouds; four-armed; holding a lotus; mace; conch (shankha) and chakra (wheel). Vishnu is also described in the Bhagavad Gita as having a 'Universal Form' (Vishvarupa) which is beyond the ordinary limits of human perception or imagination.