The Pitris (Sanskrit: पितृ, the fathers), are the spirits of the departed ancestors in Hindu culture. They are often remembered annually.
The most complete accounts about the Pitṛs are found in the Vayu Purana and Brahmanda Purana and both are practically identical. The account in the Harivamsha is shorter but agrees closely with them. The similar but brief accounts are also found in the Matsya Purana and Padma Purana. According to these accounts there are different classes of the Pitṛs and they have different origins, forms, grades and abodes. A broad distinction exists between the devāḥ pitaraḥ (divine Pitṛs) and the manuṣyāḥ pitaraḥ (Pitṛs who were deceased human beings). Some of the Pitṛs dwell in the heavenly abodes while other dwell in the netherworlds. The former who dwell in the heaven were considered as the gods and the gods were also considered as the Pitṛs.
The Pitṛs are most primeval deities and they never cease to exist. The manuṣyāḥ pitaraḥ (ancestors of human beings) can attain the same level of the divine Pitṛs and live with them in heaven by righteousness.