The Ghost Festival, also known as the Hungry Ghost Festival, 
is a traditional Chinese festival and holiday 
celebrated by Chinese in many countries.
In the Chinese calendar, the Ghost Festival is on the 
15th night of the seventh lunar month.
(which is usually 2nd or 3rd week of August)
(which is usually 2nd or 3rd week of August)
...
On the fifteenth day, the realms of Heaven and Hell 
and the realm of the living are open 
and both Taoists and Buddhists 
would perform rituals to transmute and 
absolve the sufferings of the deceased.