Visakha Puja Day is the day celebrated by Buddhists all over the world to honor the three most significant events in the Buddha's life. There are 3 significant separate events:

     1. The Buddha's birth , as one of the greatest man in the world .The Buddha taught the way to overcome suffering in life.His practice of spreading loving kindness, his compassion for all living beings, and attaining wisdom are virtues honored by all Buddhists. The Buddha was born into a royal warrior clan on the full moon day of the sixth lunar month in the Lumbini Garden 623 years before the Common Era. When the Queen of Suddodana Gautama king had permission to back to her hometown as to giving birth as they old custom in that time. One the way to her town to Tevaha she feel tried so she had a rest at the shadow of Sali tree in the Lumbini Garden is located in an area of Northern India known today as Nepal. His father was King Suddodana Gautama and his mother was Queen Siri Mahamaya. He was named Siddhattha five days after his birth.

     2. The enlightenment of Buddha where the Four Noble truth has rose ; this event took place on the full-moon day in May, when the moon is in the Visakha asterism, which is why the day is called Visakha Puja. On the Enlightenment he was sitting under the Bondi tree control his breathing in and out until he got the "yan" in each step as following. ...
  Early stage: attain "Bupenivas-sanutiyan" as the power to seeking his own and thers past lives.
  Middle stage: attain "Jetub-batayan" as he realized the impermanence of life and how living beings die only to be reborn again.
  Last stage: attain "Arsavak-kayan" as he realized the cause of all evil and suffering and how to be released from it. He understood how to end sorrow, unhappiness, suffering, old age and death. With this Enlightenment he found real peace, happiness, freedom and Buddha hood.
  At the full moon of May, forty-five years before the Buddhist Era, while sitting under the Bodhi tree at Gaya. He found his answer and attained the Enlightenment. The Great Man, now known as the Buddha, went first from Gaya to Sarnath near Benares where he gave his first sermon in the Deer Park. From then through the remaining 45 years of his life, he wandered from place to place teaching his discoveries to all whom would listen to him and organizing his followers whom renounced the world to form the Sangha.

     3. The Nibbana, the Buddha fell if while on his way to Kusinara2, capital of the Malla State. Even in the face of death his mind moved towards others. He told Ananda, his faithful attendant, to console Cunda, the poor blacksmith from whose house the Buddha ate his last meat with indigestible pork, 3 that his food offering was of great fruit and merit and that he should not blame himself for the food. On his deathbed under two Sala trees in the Sala Grove of the Mallas, he explained to his disciples that they would not be left without the Teacher for "The Doctrine and Discipline I have taught you, that shall be your Teacher, when I am gone." And his last words were; "Behold now, monks, I exhort you. Subject to decay are all component things. Work out your salvation with diligence."

     Custom of Visakha Puja Day rite
     When Visakha Puja Day come around in each year all Buddhism around the world that include Buddhist monk will gathering for a rite to commemorate the kindness and his passionate, his wisdom as one of the world light.
Every year when this important day comes around again, we Buddhists take the opportunity to pay homage to the Buddha as a way of expressing our gratitude for his goodness. Visaka Puja usually fell on the middle of May or June for Thai old lunar calendar. The rite that held on Visaka Buja can be divided into three rites:

   1. Royal rite
   2. General rite
   3. Monk rite where the monk will carry out monk rite. Most of the sermon and rite that held in Visaka Buja have the same way of Buddhism rite for Maka Buja.

Background : Visakha Puja.htm History of Buddha.htm