Guru Purnima (Sanskrit: गुरुपूर्णिमा, romanized: Gurupūrṇimā) is a religious festival dedicated to offering respect to all the spiritual and academic gurus. It is celebrated as a festival in India, Nepal and Bhutan by Hindus, Jains and Buddhists. This festival is traditionally observed to honour one's chosen spiritual teachers or leaders. It is observed on the full moon day (Purnima) in the month of Ashadha (June–July) according to the Hindu Calendar.The festival was revived by Mahatma Gandhi to pay tribute to his spiritual guru, Shrimad Rajchandra. It is also known as Vyasa Purnima, for it marks the birthday of Veda Vyasa, the sage who authored the Mahabharata and compiled the Vedas
The word guru is derived from the Sanskrit root words, gu and ru. Gu means "darkness" or "ignorance", and ru means "dispeller."
Therefore, a guru is the dispeller of darkness or ignorance.

We celebrate Guru Purnima in the Hindu month of Ashadha, which is either in June or July. Guru Purnima is also commonly known as Vyasa Purnima. It is because it is on that day Veda Vyasa was born. As per Karma Yoga, Guru Purnima is a day of worshipping our Gurus for sharing their knowledge and wisdom by not considering the monetary benefits.

There are different stories associated with the celebration of Guru Purnima. As per the Yogic tradition, it was the day Lord Shiva became the first Guru. Around 15000 years back, a yogi came to the Himalayas with extraordinary abilities. He continued to stay there, and people came to visit him. When he opened his eyes, seven men asked him to teach them to experience what he was undergoing. However, the yogi did not reply, and he closed his eyes again. When he opened them 84 years later, the seven disciples were still there. Understanding their need for wisdom, on a full moon day, he became the first Guru. He imparted his knowledge to the seven men who became the Sapta Rishis. They traveled across the world to spread his wisdom or the seven aspects of Yoga. Each one of them explained one feature of Yoga. Based on the day when Lord Shiva ascended as the first Guru, we celebrate Guru Purnima.

Another story associated with Guru Purnima is that it was the day Krisha Dwaipayana Vyasa was born. His parents are Parashara and Satyavati. Vyasa, as a young man, collected the Vedas and divided its hymns into four parts. They became Rig Veda, Yajur Veda, Sama Veda, and Atharva Veda. He taught portions of the Vedas to his four main disciples. They are Paila, Jaimini, Sumantu, and Vaisampayana. We celebrate the birth of Vyasa based on the contributions he has made to the world as a teacher. In Buddhism and Jainism, we can find similar stories that we can associate with Guru Purnima. The primary focus of celebrating Guru Purnima is to worship and pay respect to our teachers.

Another story associated with Guru Purnima is that it was the day Krisha Dwaipayana Vyasa was born. His parents are Parashara and Satyavati. Vyasa, as a young man, collected the Vedas and divided its hymns into four parts. They became Rig Veda, Yajur Veda, Sama Veda, and Atharva Veda. He taught portions of the Vedas to his four main disciples. They are Paila, Jaimini, Sumantu, and Vaisampayana. We celebrate the birth of Vyasa based on the contributions he has made to the world as a teacher. In Buddhism and Jainism, we can find similar stories that we can associate with Guru Purnima. The primary focus of celebrating Guru Purnima is to worship and pay respect to our teachers. Guru Purnima is a day of gratitude. On this auspicious day, we can be thankful for the knowledge and wisdom shared by our Gurus. However, we cannot provide anything in return that equals what our Gurus have given us. The only way to enhance what we have attained or learned from our Gurus is to share the light of knowledge with others. It is always about passing on wisdom to others and keeping it alive. For Guru Purnima, we are not celebrating an individual teacher or Guru. Here, we are trying to pay our respects to all the spiritual and academic Gurus who have helped us grow.

As per Buddhist tradition, the festival is celebrated by Buddhists in honour of the Buddha, who gave his first sermon on this day at Sarnath, Uttar Pradesh, India. In the yogic tradition, the day is celebrated as the occasion when Shiva became the first guru, as he began the transmission of Yoga to the Saptarishis.In Vedic Hindu tradition, the day is celebrated in honour of the sage Vyasa, who is seen as one of the greatest gurus in ancient Hindu traditions and a symbol of the guru-shishya tradition. Vyasa was not only believed to have been born on this day but also to have started writing the Brahma Sutras on ashadha sudha padyami. Their recitations are a dedication to him and are organised on this day, which is also known as Vyasa Purnima. The festival is common to all spiritual traditions in Hinduism, where it is an expression of gratitude toward the teacher by his or her disciples. Hindu ascetics and wandering sanyasis observe this day by offering puja to their guru, during Chaturmasya, a four-month period during the rainy season, when they choose seclusion and stay at one chosen place; some also give discourses to the local public.Students of Indian classical music and Indian classical dance, who also follow the guru shishya parampara, celebrate this holy festival around the world.