Vesak day - Buddha Purnima or Buddha Jayanti is celebrated to mark the birth of Lord Buddha, the historical founder of Buddhism. Vesak day is the most sacred festivals of Buddhist. Buddha is one of the greatest spiritual teachers of mankind and known as the "Light of Asia". Buddha Purnima falls on the full moon day in the Hindu month of Vaisakh (April/May). This day is a thrice blessed day. In addition to Lord Buddha's birth on the Full Moon day, Buddha achieved enlightenment and nirvana (salvation) on the same day (on the Full Moon day-full moon occurs when the geocentric apparent longitudes of the Sun and Moon differ by 180 degrees; the Moon is then in opposition with the Sun). Thus, His birthday, enlightenment day and death anniversary (nirvana), all happened in the month of Vaiskh, on a full moon day in April/May.

However, in Mahayana countries like Japan, these three events of Buddha are observed on separate days. In some countries the birth date is April 8, the Enlightenment date is December 8, and the death date is February 15.

Gautama, Buddha was born in 623 BC in the northeastern region of ancient India; now in Lumbini, Nepal in a royal family. His name was Siddhartha and he was the only son of the great King of Kapila vasthu, Suddhadhana and Queen Mahamaya. He married Yashodhara at the age of sixteen. Though he brought up amidst the luxuries of a palace, the young prince noticed the grate suffering of people, their poverty, pain and tears. Also he noticed the suffering of poor people and soldiers due to frequent wars initiated by kings, only to expand their kingdom.

Prince Siddhartha went into deep meditation under a Bodhi tree near Gaya, until he finally attained enlightenment on the full moon day of Vaishakh. He was then 35 years of age and thereafter became known as Gautama, the Buddha.. ". Buddha means "enlightened one" - someone who is completely free from all faults and mental obstructions. He gave his first sermon in Sarnath, near the holy city of Varanasi, India, to his followers who formed a Sangha, also on the Vaishakh Purnima. His passing away (Maha parinirvana) was on BC 544 at the age of 80 on the full moon day in the month of Vaisakh.

Buddhism describes sorrow and desires are the main cause of all the evil and suffering of this world. Lord Buddha advocated the Eightfold Path consisting of precepts like right conduct, right motive, right speech, right effort, right resolve, right livelihood, right attention and right meditation to gain mastery over suffering. Buddha has eighty-four thousand teachings. All these teachings and the inner realizations of them constitute Buddhism. It is only after following this path one can reach the ultimate aim of Nirvana or the extinction of self and freedom from the cycle of rebirth.

Buddhism is the fourth-largest religion in the world behind Christianity, Islam, and Hinduism. Buddhism has largely flourished in countries out side of India throughout the Far East in Asia, though Buddhism originated in India. Estimates of the number of Buddhist followers are uncertain. Depending on the source, the number of Buddhists in the world ranges from 230 to 500 million or more, mostly in Asia. Estimates are uncertain and under dispute because difficulties in defining who counts as a Buddhist and similarity of beliefs of Taoism, Confucianism, Shinto and traditional religions or Shamanism, animism etc and also they have no congregational memberships. Buddhist countries like India, Myanmar, Cambodia, Laos, Thailand, Japan, Burma and Sri Lanka celebrate this festival with special fervour.

The Buddha is considered the ninth avatar of Lord Vishnu.