The Mid-Autumn Festival on July 15th of the lunar calendar, commonly known as "Ghost Festival", lasts for one month from July 1st to July 30th of the lunar calendar.
Buddhism and Taoism have different interpretations of the significance of this festival. Buddhism emphasizes filial piety; Taoism focuses on "Purdue" those lonely souls released from the underworld.
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The ceremony for Buddhists to celebrate Mid-Autumn Festival is called "Orchid Festival". Celebrating the Mid-Autumn Festival is not only to pay homage to their dead relatives, but also to commemorate Mulian and praise his filial days as a Buddhist.
The story of Mulian's saving his mother comes from the Tripitaka (Buddhism introduced from India). According to the records in the Tripitaka, Manglietia saw her dead mother, Si Liu Niang, tortured by a group of hungry ghosts after suffering in the underworld. Manglietia gave her a bowl of vegetable rice, but the vegetable rice was taken away by the hungry ghost. Mu Lian turned to the Buddha for help, and the Buddha was moved by Mu Lian's filial piety and presented the Lanjing. According to the instructions, Mulian provided her mother with a vegetarian meal filled with rare fruits in a orchid pot on July 15th, and the hungry mother finally got food. Buddhists hold a grand "Orchid Club" every year to commemorate Manglietia's filial piety.
Taoism believes that since the first day of the seventh lunar month, the underworld has opened the gate of hell and released ghosts to the world for sacrifice. In order to avoid the interference and harm of ghosts and gods, the "Central Plains Purdue" was set up on July 15 to provide food and burn ghost paper to appease those lonely souls who have no owners.