Lord Vishnu also referred to as Narayana or Hari is worshipped as the Supreme God and is believed to have incarnated in different forms to annihilate the evil and restore Dharma and righteousness. The Lord is all pervasive and is the sustainer of the universe and the whole cosmic creation among the Trinity- Lord Brahma, Lord Vishnu and Lord Shiva. He represents Sattva Guna through which everything is sustained.

According to the Indian Puranas, Vishnu is described possessing the divine blue colour of water-filled clouds and four arms resting on his Sheshnaag. The Bhagavad Gitadescribes him as a 'Universal Form' or Vishvarupa that is beyond the ordinary limits of human perception.

Vishnu's eternal and supreme abode is Vaikuntha, the realm of eternal bliss. Within the material universe his abode is the Ksheera Sagara, where he reclines and rests on Ananta Shesha. The Lord is most commonly worshipped in his Dasavatara forms. Lord Vishnu in Rig Veda has also been accorded the highest place. Among the 1000 names of the Lord, the name Vishnu is the second name in the Vishnu Sahasranama.

Etymology of Lord Vishnu
According to the 1st millennium BCE medieval scholars Yaska and Medhatithi, the word Vishnu means "the one who enters everywhere" and “that which is free from fetters and bondages is Vishnu”. Thereby connoting that Vishnu is one “who is everything and inside everything”. Vishnu means "all pervasive".

Incarnations of Vishnu
According to the Indian Puranas, Lord Vishnu possesses the divine power that helps during the various stages of human evolution by incarnating on earth in different forms. The 10 most famous incarnations of Vishnu are collectively known as the 'Dasavatara.' According to the Bhagavad Gita the purpose of incarnation of Vishnu is to re-establish Dharma or righteousness and destroy injustice. The list is also included in the Garuda Purana.

In the list of 10 avatars the majority of avatars are categorised as 'lila-avatars' and the first four are believed to have appeared in the Krita Yuga. The Treta Yugawitnessed the incarnation of the next three, the eighth incarnation in the Dwapara Yuga while the ninth incarnation in the Kali Yuga. The 10 avataras are Matsya Avatar (fish), Kurma Avatar (tortoise), Varaha Avatar (boar), Narashima Avatar (the man lion), Vamana Avatar (the dwarf), Parasurama (the angry man), Lord Rama (the perfect human), Balarama and Lord Krishna (the divine statesman). The 10th avatar, which is yet to appear, is Kalki, he is expected towards the end of this present age of decline, as a person on earth, seated on a white horse.

Minor Incarnations of Lord Vishnu
The minor incarnations includes several other incarnations of Lord Vishnu besides his Dasavatara forms. These include Kapila, Dattatreya, Hayagriva, Hayashirsha, Yajna, Lord Dhanwantri, Ved Vyas, Rishabha, Nara and Narayana, Balarama, Narada, Varadaraja, Manmatha, Prithu and Mohini.

Legends of Lord Vishnu
Lord Vishnu worshipped as the Supreme Being in Vaishnavism is associated with several legends and mythological fables. The legend of Lord Vishnu and Sage Bhrigu recites about the test of the Lord taken by the sage to decide upon the supremacy of the Lord among the trinity, Lord Brahma, Lord Vishnu and Lord Shiva. The next legend of Lord Vishnu and Shukrh states about the former being cursed by the later for killing his mother. According to the third legend of Lord Vishnu and Vrinda where the later cursed the lord for deceiving her and killing her husband Jalandhara. As per the Legend of Lord Vishnu and Bhasmasura the later was blessed with the boon of turning to ashes anyone on whose head he placed his hand. The legend of Lord Vishnu and Brahma narrates about the former preaching about the modesty and humility.

Weapons of Lord Vishnu
Lord Vishnu worshipped as the preserver of the creation is seen possessing four hands. With his upper right hand he holds a discus or the chakra that symbolises the mind, with his upper left hand he holds a bow representing the causal power of illusion, and with his lower right hand he holds a conch. The conch shell is spiral and symbolizes all of interconnected spiralling cyclic existence, while the discus symbolizes him as that which restores dharma with war if necessary when the cosmic equilibrium is overwhelmed by evil. One of his arms sometimes carries a gadda or a club and mace which symbolize authority and power of knowledge. In the fourth arm, he holds a lotus flower which symbolizes purity and transcendence.

Idols of Lord Vishnu
Lord Vishnu commonly venerated as Narayana or Hari is also worshipped by his devotes in different forms. Several idols of the lord are installed in temples and adorned by the pilgrims. Some of the idols of the Lord are Vasudeva, Samkarshana, Pradyumna, Aniruddha, Madhava, Govinda, Vishnu, Kesava, Upendra, Hari, Purushottama, Jagannatha, Janardana, Achyuta, Jagannatha, Hamsa, Vishwarupa, Lakshmi Narayana, Yajnavaraha, Madhusudana, Shridhara, Harshikesha, Padmanabha, Damodara, Vaikunth Anatha, Trailokya Mohana, Ananta, Adimurti, Lakshmi, Bhu and Nila, Mahavishnu and Shayanavishnu.

Attendants of Lord Vishnu
Lord Vishnu, the preserver and sustainer of life is attended, revered and flanked by several attendants such as Garuda, Ananta, Vishvakshena, Sudarshana and Jaya-Vijaya.

Consorts of Lord Vishnu
The legends of Vishnu suggest that the Lord had three wives Goddess Saraswati, Goddess Lakshmi and Goddess Parvati. He however, gave away Saraswati and Parvati to Lord Brahma and Lord Shiva respectively. Besides, Bhudevi is also regarded as the consort of the Lord.

Lord Vishnu in Other Religions
Beyond the culture and religion of Hinduism, Lord Vishnu is referred to as Gorakh in the scriptures of Sikhism. The Chaubis Avatar text of Sikhism lists the 24 Avatars of Lord Vishnu which also includes Lord Krishna and Lord Rama of Hinduism. Similarly, the Dasam Granth includes Vishnu mythology mirror that is found in the Vaishnav tradition. In Hinduism, there are some Hindus who consider Lord Buddha as an incarnation of Lord Vishnu, while in some of the Buddhist cultures Lord Vishnu is worshipped as the custodian deity of Sri Lanka and the protector of Buddhism. It is known that the Sinhala Buddhist tradition encourages the worship of Lord Vishnu as a part of the Theravada Buddhism.

Iconography of Lord Vishnu
Lord Vishnu’s iconography shows him with dark blue, or blue-grey or black coloured skin, and as a well dressed jewelled man. He is typically shown with four arms, but there are also two armed representations which are discussed in Hindu texts and artworks. In his four arms, Lord Vishnu is known to hold a chakra, conch shell, mace and a lotus respectively. The items he holds in various hands varies, giving rise to 24 combinations of iconography, each combination representing a special form of Vishnu. Each of these special forms is given a special name in texts such as the Agni Purana and Padma Purana. Lord Vishnu’s iconography either portrays him in a standing pose, seated in a yoga pose or simply reclining.

Temples of Lord Vishnu
Some of the earliest surviving grand Vishnu temples in India have been dated to the Gupta Empire period. Archaeological evidence suggests that Vishnu temples and iconography probably were already in existence by the 1st century BCE. The most significant Vishnu-related epigraphy and archaeological remains are the two 1st century BCE inscriptions in Rajasthan which refer to temples of Sankarshana and Vasudeva, the Besnagar Garuda column of 100 BCE which mentions a Bhagavata temple, another inscription in Naneghat cave in Maharashtra by a Queen Naganika that also mentions Sankarshana, Vasudeva along with other major Hindu deities and several discoveries in Mathura relating to Vishnu, all are dated to about the start of the common era.