Chinese people usually put up Spring Festival couplets on front gates of their houses during holidays or on auspicious occasions. However, Spring Festival couplets were not so called in the first place. Instead, they used to be called peach wood charms.
It is said that long long ago, there was a mountain named Dusu in the East Sea. On the mountain there was a huge peach tree whose roots stretched outward, covering an area of 3,000 square kilometers. On the northeast top of the tree grew an arc-shaped branch bending down the ground, looking like a gate. To prevent evils and ghosts from disturbing the man's world, the Supreme Deity sent two divine generals to guard the branch and ordered every evil spirit or ghost should go through this gate-like branch whenever they wanted to go down the mountain. Due to this reason, people thought peach wood could be used to put down evil things and began to decorate their gates with two carved deity figures made of peach wood. Later on, they thought it time-consuming to carve and simply hang peach wood boards and drew the figures on them. But some people thought it still very troublesome and began to write some auspicious words or drew charms on two pieces of paper and put them on their gates. Thus Spring Festival couplets came into being.
During the Five Dynasties (907-960), people started to write antithetical couplets as their peach wood charms. It is said that once Emperor Zhu Yuanzhang of the Ming Dynasty made a tour in disguise, he saw a butcher's house did not put up Spring Festival couplets and then wrote one for him. Since then, putting up Spring Festival couplets became a fashion throughout the country.
Although several hundred years have passed by, the use of Spring Festival couplets are still very popular in China, not only during the Spring Festival but also on other important occasions like weddings and funerals. And Spring Festival couplets are hung not only on front gates, but also on walls and beams and in setting rooms.
在今天的中国，从城市到乡村，每逢春节或其他喜庆的日子，仍然十分流行在门扇上贴红艳艳的"对子"的风俗。但在古代，人们是把"对子"称作"桃符"的。
为什么把"对子" 叫做 "桃符"呢？传说很久以前，在东海有一座很大的度朔山，山上有一棵大桃树，树根向四周伸开，方圆足有3000多里。桃树的东北头有一根拱形枝干，弯弯的树梢垂到地面，像一扇大门。山上的各种妖魔鬼怪，出山必须经过这个门口，天帝特地派了神荼和郁垒两个神将把守在门口，不让恶魔出去骚扰人间。由此，人们认为桃木具有镇邪的作用。民间便盛行用桃木雕刻出两个神像装饰在自己的大门上，用来镇压邪鬼。后来，人们简化为在两块桃木板上画神像来代替神像雕塑，这叫做"桃板"。以后更简化了，只把写有"神荼"、"郁垒"桃板钉在门上就行了。最后，干脆就用两张纸或画上两个神将，或画上符咒，或写上吉利话，贴在门上，这就叫"桃符"。
到了五代，桃符上渐渐开始用联语。明朝时，传说明太祖朱元璋一次微服出巡时，见一阉猪的人家门上没有贴春联，就为他家写下了"双手劈开生死路，一刀割断是非根"的春联。自此之后，春联之风更为盛行。
尽管历史又延续了千百年，但春联的应用在中国却越来越广泛。春联不仅仅在过年时贴，平时，逢到婚丧喜庆等活动也有贴"对子"的，而且所贴的范围也不仅仅局限于门板了，厅堂、墙壁、梁柱上都可以贴。人们将这种联语统称为"楹联"或"对联"。
