In China, there is a long history of using knots(结) for decoration(装饰品) on clothes or to hang on a wall.
Chinese knots can be in different shapes. Each shape has its own symbolic(象征性的) meaning, and nowadays you can find them as gifts for special celebrations, and decorations on clothes. Each kind of knot is named after its shape or the symbolic meaning that it carries. Though knots are made in many kinds of colors, red is the most popular color because red means good luck in China.
It's known that knots were used for artistic(艺术的) decoration and to express thoughts and feelings in the Tang Dynasty(618~907). And the traditional art form was carried on by generations as part of their culture.
Even today, Chinese knots are rich in symbolic meaning. Knots mean love and marriage in Chinese culture. In ancient times and even now, lovers may give a knot as a symbol of their love. The "true love knot" and the "double happiness knot" are given or used at weddings(婚礼) to express love and getting old together.
Also, knots are still used if they wear traditional Chinese clothing. They are used as good luck charms(护身符). They are also used as jewelry(珠宝) such as earrings and necklaces. They are sold as handicrafts(手工艺品), too.