Loi Krathong (or Loy Krathong, Thai: ลอยกระทง) is a festival celebrated annually throughout Thailand, certain parts of Laos and Malaysia. Penang is celebrated on the full moon of the 12th Lunar month in which devotees pray to the Water Goddess as well as repent for what they have done.
Loi Krathong is held on the full moon of the 12th month in the traditional Thai lunar calendar. In the western calendar this usually falls in November. "Loi" means "to float" and a "Krathong" is a raft, about a hand span in diameter, traditionally made from a section of banana tree trunk. A raft has been developed to be made of bread or sometimes made of styrofoam.
The reason for using bread is to protect the environment,since having many rafts in the river can create a huge water pollution problem. Bread will eventually become food for fish and other animals in the river. Even though banana leaves are biodegradable, it takes longer to be degraded than a bread. Therefore, bread is the most environmental friendly choice to make a raft whereas foam is not recommended at all. A raft is decorated with elaborately-folded banana leaves, flowers, candles, incense sticks etc..