Mythology about Nian

Chinese New Year is called as Spring Festival too. Spring Festival features wearing new clothing, eating dumplings, having reunion dinner, posting spring scrolls on windows and doors etc. Some picture posted on door is called door-god, which is very fearful. Why do people like to post an ugly picture on door?  There is a tale about Nian. Nian means year. For example I had studied four years in Jiangsu province. But there is another meaning. According to tales and legends, Nian is a mythical beast. Nian would come on the first day of New Year to eat livestock, crops, and even villagers, especially children. To protect themselves, the villagers would put food in front of their doors at the beginning of every year. It was believed that after the Nian ate the food they prepared, it wouldn’t attack any more people. One time, people saw that the Nian was scared away by a little child wearing red. The villagers then understood that the Nian was afraid of the colour red. Hence, every time when the New Year was about to come, the villagers would hang red lanterns and red spring scrolls on windows and doors. People also used firecrackers to frighten away the Nian. From then on, Nian never came to the village again.