2012-12-6 16:00:00 From: http://traditions.cultural-china.com/en/211Traditions474.html
The Spring Festival, or Chinese New Year, is the most important festival for Chinese people. Legend has it that in ancient times, there was a monster called "Nian" ("year") that would come out to eat people and animals on the eve of every New Year. To avoid the monster's attack, people would flee to the depth of the mountains and call this day "Nian Guan" (meaning "the Pass of Nian"). On one New Year's Eve, there came an old beggar in Peach Blossom Village, where an old lady gave him some food and asked him to hide himself in the mountain to avoid the monster Nian. The old man promised that he could drive the monster away as long as he was put up for the night at the old lady's home. Being unable to persuade the old man into hiding in the mountain, the old lady went alone. In the middle of the night, the monster Nian dashed into the village. He trembled and cried when he saw the red paper on the door of the old lady's house, which was brightly lit. Just as the monster reached the entrance, there came blasting sounds that prevented him from moving any further. At that time, the old man, wearing a red robe, opened the door and the monster was scared away. Actually, the color red, firelight and blasting sounds were the things the monster feared most. After that, on every New Year's Eve, every household would paste red couplets, let off firecrackers and light candles as well as stay up the whole night to avoid being attacked by the monster. This is how these customs came into being.