The full moon of Vaishakha, in Sri Lanka, India, Nepal and Southeast Asia. The Buddha's birth, enlightenment and passing, all on this full moon by Theravada tradition; the UN's Day of Vesak since 1999. Vesak (Pali: Vesākha; Sanskrit: vaiśākha), also known as Buddha Jayanti, Buddha Purnima, Visak Bochea and Buddha Day, is a holiday traditionally observed by Buddhists in South Asia and Southeast Asia, as well as in Tibet and Mongolia. It is among the most important Buddhist festivals. The festival commemorates the birth, enlightenment (Pali: Nibbāna, Sanskrit: Nirvāṇa), and death (Parinirvāna) of Gautama Buddha in Theravada, Tibetan Buddhism, and Navayana. The name Vesak is derived from the Pali term vesākha or Sanskrit vaiśākha for the lunar month of Vaisakha, which is considered the month of Buddha's birth. In Mahayana Buddhist traditions, the holiday is known by its Sanskrit name (Vaiśākha) or variants of that. In the East Asian tradition, a celebration of Buddha's Birthday typically occurs around the traditional timing of Vesak, while the Buddha's awakening and death are celebrated as separate holidays that occur at other times in the calendar as Bodhi Day and Nibbāna Day. In the South Asian tradition, where Vesak is celebrated on the full moon day of the Vaisakha month, the Vesak day marks the birth, enlightenment, and the ultimate death of the Buddha. Wiki link Dates computed: Theravada full moons on the South Asian lunar calendar (New Delhi), East Asian days on the Chinese calendar (China's time), Japan's on fixed dates. Text: Wikipedia (CC BY-SA).