Guru Purnima is a festival traditionally celebrated by Hindus and Buddhists.On this day, disciples offer puja or pay respect to their Guru (Spiritual Guide). It falls on the day of full moon, Purnima, in the month of Ashadh of the Shaka Samvat, Indian national calendar and Hindu calendar.
Traditionally the festival is celebrated by Buddhists in the honor the lord Buddha who gave His first sermon on this day at Sarnath, Uttar Pradesh, India. While Hindus celebrate it in the honour of the great sage Vyasa, who is seen one of the greatest gurus in ancient Hindu traditions, and a symbol of Guru-shishya parampara, the Guru disciple tradition.
Vyasa was believed to have started writing the Brahma Sutras on ashadha sudha padyami and ends on this day, hence their recitations as a dedication to him, are organised on this day, which is also known as Vyasa Purnima.