Bodhi Day is a Buddhist winter holiday - traditionally occurring on the 8th day of the 12th lunar month - that commemorates the day that Siddhartha Gautama experienced enlightenment and found the roots of suffering after sitting and meditating under a Pipul tree (ficus religiosa, a kind of fig tree which attains great size and venerable age). When Siddhartha was enlightened, he became a Buddha ("Awakened One"), finally found the answers he sought, and experienced Nirvana.
Enlightenment in Buddhist tradition means transcending suffering and awakening to one's true nature and the true nature of all being. In Sanskrit, the word for "enlightenment" is "bodhi", which is the basis for the term "Buddha" and means "awakened".
This holiday is not as popularly celebrated as other Buddhist holidays, but it is observed in many mainstream Mahayana traditions including Zen and Shin Buddhist schools. Bodhi Day is a day of remembrance and meditation - a time to focus not only on one's own path to enlightenment, but also to consider Siddhartha's achievement of enlightenment and what this means for Buddhism today. A celebration of a transformation and the beginning of a faith - not entirely unlike the ideas behind Christian Christmas.
Historically, Siddhartha Gautama, prince of the Shakya clan, left his home and all his earthly possessions at the age of 29 to search for the Meaning of Life and to search for the reasons why people born, why they die, and why they suffer. After seven years of discipline and asceticism under the tutelage of several spiritual teachers, he still felt as though he had learned nothing. On the 8th day of the 12th month in 596 BC, he woke enlightened after 7 days of meditation beneath a Pipul tree.
A Bodhi Day celebration can come in many varieties, depending on the Buddhist school and the cultural background of the practitioner.
Practitioners may hang up strings of multi-colored lights to represent the many paths to enlightenment. Beginning on December 8th, they will turn on these lights every evening for thirty days. In some homes, Buddhists will have a ficus tree strung with these lights, upon which they will hang three shiny ornaments to symbolize the Three Jewels - the Buddha, the Dharma, and the Sangha.
A traditional meal of rice and milk is usually eaten on this holiday, with the significance that Sujata offered this meal to the Buddha when he awakened from his meditation to help him regain his strength. Though in recent years, some Buddhist families have made more modern amendments by making cookies in the shape of a tree to symbolize the Bodhi tree. Or they may make cookies in the shape of leaves - the leaves of the Bodhi tree are heart-shaped, so using a Valentine's Day cookie cutter works well for this.
However, the main theme of celebration comes in the form of meditation and self-reflection, and sharing Buddha's message of appreciation and compassion for others. If gifts are given, they're genuinely hand-made and given to one's teachers and spiritual influences.
To watch a video about this holiday, follow this link.
Note: The above information was researched for the sake of education and appreciation, in a hope to promote cross-cultural pollination, tolerance, and peaceful understanding. If I got anything wrong or missed anything, please feel free to comment. I love to learn and I'd like this to be as factual as possible.