China's four classical toys: Jiuhuanhuan, Huarong Road, Tangram and Lubanzuo Jiuhuanhuan: The folk toy Jiuhuanhuan in China originated in the Warring States Period, and was made into a ring shape with metal wire, which was sleeved on a horizontal plate or various frames and connected by a ring handle (see Jiuhuanhuan Figure and real objects). When playing, repeat the operation according to a certain procedure, so that the rings can be untied separately or combined into one. Nine-ring chain is very popular, with various forms and specifications. In addition to the nine rings, there are similar snake rings, flower basket rings and thirteen rings. , also known as the nine-ring chain. In particular, the solution of nine chains corresponds strictly to the cyclic code invented by American mathematician FrankGray, which can be used for radio communication. Ancient toys contain modern technical principles, which can not help but make people wonder that the decomposition and integration procedure of the nine chains is helpful to inspire people's wisdom, interesting and deeply loved by children and the elderly. Huarong road, Cao Cao fled quickly, and the small soldiers chased him diligently and passed the customs. They had a four-star party, and Guan Yu was tempted to let Cao Cao settle it. Cao: Huarong Road sees the truth. In a box, there are four pieces, Cao Cao, five tiger generals and four soldiers, which are required not to overlap and need to be dismantled. Finally, it is successful to move Cao Cao from the top of the chessboard to the center below. The game configuration is: a chessboard and two pieces. Game method: move the wooden block in the chess box, and finally Cao Cao moves from the gap on the edge of the chess box. Tangram: Also called Tangram, it is a famous jigsaw puzzle in China. Because of its scientific design, ingenious conception and endless changes, it can activate the thinking in images, especially inspire children's wisdom, so it is very popular. After it was spread abroad, it became popular all over the world, and it was called "Tangtu" and "the drawing board of China". There are many kinds of jigsaw puzzles, and here is the most conventional jigsaw puzzle in China. Luban Lock: According to legend, in the Spring and Autumn Period, Lu craftsman Luban made a detachable toy out of a piece of wood to test his son's IQ and told him to take it apart. His son worked all night and finally finished it. This toy was called Lubanzo by later generations. In fact, this is a legend. Luban lock, also known as Kongming lock, originated from the tenon-mortise structure pioneered by ancient buildings in China.