The most fundamental of Hindu deities, is the Trinity of Brahma, Vishnu and Shiva - popular deities include Ganesha, Krishna, Hanuman and goddesses like Lakshmi, Durga,Saraswati.
Lord Satyanarayana is another form of Lord Vishnu.
Satya Narayan is the Narayan form of Lord Vishnu. The Lord in this form is considered an embodiment of truth. Satyanarayana is worshipped commonly by Hindus in their homes with family and friends, usually on a full moon (purnima) day of the month. In this puja called Satyanarayana Pooja, people worship by reciting the gracious story of Lord Satyanarayana. This story was originally told by Lord Vishnu himself to the sage Narada for the benefit of humankind.
The Lords Satyanaryana grace is described in a Hindu book called Skanda Purana. He has four hands like Lord Vishnu, however, his fourth hand does not hold a lotus rather it is extended upward to bless people
This puja is conducted to ensure abundance in ones life. Many people carry out this puja immediately after or along with an auspicious occasion like a marriage or moving into a new house or any other success in life. The satyanarayan puja can be performed on any day. It is not a puja confined to any festivities. But Poornima (full moon day) or Sankranti are considered to be most auspicious day for this puja. Performing this puja in the evening is considered more appropriate. On the day of the puja, the devotee has to fast.
The prasad for this vrita is known as Sapaad which is prepared thus: Take an equal measure of rava, Milk, Ghee, Banana, Sugar ( the measure should be 1 1/4 or multiples thereof ) cook it till all mix into a paste.