Full moon days in Hindu calendar are known as Purnima or Pournami. Pournami that falls in the month of Jyeshta is called as Jyeshta Pournami.
South Indian people called it as Pournami, whereas North Indians called it as Purnima.
Apart from festivals, Pournami is a very important and auspicious day in Hindu calendar.
Jyeshta Purnima is also known as Snan Purnima or Jagannatha Purnima. Snan yatra is celebrated in Puri Jagannath temple.
Vat Savitri vrat is observed on this day by north Indian married women, to prolonging their married life.