Today is Krishna Janmashtami, the annual celebration in the Hindu calendar of the birthday of Lord Krishna. Because of the complex intricacies of the Indian calendar’s structure and workings, the precise date of this popular Hindu holy day and festival can fall anywhere between roughly mid-August and mid-September. For example, last year (2011), the holiday fell upon August 22, while in the previous year (2010) it was instead on September 1.

This year, Janmashtami happens to occur on Friday, August 10.

The nature of the celebrations varies from place to place within India (and beyond), ranging from fasting, midnight vigils, chanting mantras, singing hymns, and reading scriptural passages to dances, games and competitions, elaborate re-enactments of Sri Krishna’s deeds (Sri is an epithet meaning “Holy”), and other traditional Hindu celebratory festivities.

Lord Krishna is revered by many if not most Hindus as an avatar (“descent”) — that is to say, an incarnation or manifestation — of Vishnu (one of several traditional Hindu forms, aspects, or ways of conceptualizing of the Supreme Being).

Whereas Christianity recognizes only one single divine incarnation of God in human form (as Jesus Christ), and whereas both Judaism and Islam deny that God ever becomes physically incarnate on earth (even regarding the very idea of such a thing as idolatrous and blasphemous), Hinduism by contrast traditionally recognizes at least ten major avatars of Vishnu.

Of these divine avatars of Vishnu (God), perhaps the best-known and best-beloved is Krishna, who figures prominently in such important and popular Hindu scriptures as the Bhagavad Gita and the Bhagavata Purana (sometimes referred to as the Srimad Bhagavatam). According to Hindu tradition, Krishna lived from 3228 BC (his birthdate being celebrated today as Janmashtami) until 3102 BC.

Hinduism is perhaps the world’s oldest major living religion. It is also the world’s third largest religion (after Christianity and Islam). With nearly a billion followers worldwide, Hindus comprise about 13% of humanity. The vast majority of Hindus live in India, the land of Hinduism’s birth, where it remains overwhelmingly the majority faith (India’s vast population of over one billion people is 80% Hindu).

Beyond India, Hindus are scattered everywhere around the globe, but usually in much smaller numbers. Except for Nepal and Mauritius, where Hindus represent 80% and 54% of those respective populations, Hinduism is a minority religion elsewhere. For instance, the Hindu community within the United States currently numbers just over one million (only 0.4% of the U.S. population).

Be that as it may, today is an important holiday (quite literally a “holy day”) to Hindus worldwide. And so, wherever they might be, I would like to take this opportunity to wish them all Happy Janmashtami!