Avatar (from Sanskrit अवतार) is a deliberate descent of a deity to earth, or a descent of the Supreme Being (i.e., Vishnu for Vaishnavites), and is mostly translated into English as “incarnation”, but more accurately as “appearance” or “manifestation”.
The concept of avatar within Hinduism is most often associated with Vishnu, the preserver or sustainer aspect of God within the Hindu Trinity or Trimurti or the one and only supreme God for followers of Vaishnavism.
Vishnu’s avatars typically descend for a very specific purpose. An oft-quoted passage from the Bhagavad Gita describes the typical role of an avatar of Vishnu—to bring dharma, or righteousness, back to the social and cosmic order:
यदा यदा हि धर्मस्य ग्लानिर्भवति भारत ।
अभ्युत्थानमधर्मस्य तदात्मानं सृजाम्यहम् ॥
परित्राणाय साधूनां विनाशाय च दुष्कृताम् ।
धर्मसंस्थापनार्थाय सम्भवामि युगे युगे ॥
The descents of Vishnu are also integral to His teaching and tradition, whereas the accounts of other deities are not so strictly dependent on their avatar stories. Although it is usual to speak of Vishnu as the source of the avatars, within the Vaishnavism branch of Hinduism Narayana, Vasudeva, and Krishna are also seen as names denoting divine aspects which descend as avatars.
The Bhagavata Purana describes Vishnu’s avatars as innumerable, though there are ten incarnations (Dashavatara, Sanskrit: ten avatars) that are widely seen as his major appearances. Krishna and Rama are the two mostly widely known and worshiped avatars of Vishnu, with their stories told in the two popular epics, the Mahabharata and the Ramayana. Different lists of Vishnu’s avatars appear in different texts, including: the dasavatara from the Garuda Purana; lists of twenty-two, twenty-three, and sixteen avatars in the Bhagavata Purana; thirty-nine avatars in the Ahirbudhnya saṃhitā; the dasavatara again in Agni Purana; the first eight of the dasavatara in Padma Purana.
The different avatars being;
Matsya, Kurma, Varaha, Narasimha, Vamana, Parshuram, Lord Ram, Shri Krishna and Kalki(yet to come)!