Ci Yuan said: lock, the old is called the key, now it is called the lock. "The "Ci Hai" is expressed as: "The sealing device that can only be excused with a key".

The initial lock was a relatively simple organ unit set up by the owner to prevent others from opening. The small compression type door lock is applied to the door. The simple lock is the door bolt. There were stone locks in ancient China, which had no keys and were bound by rope locks or ropes. During the Shang and Zhou dynasties, the private ownership of production factors further developed, the disparity between the rich and the poor was further increased, and social problems were very prominent. In addition, the switchgear electromagnetic lock smelter was technically perfect and was immediately used in the field of lock making. Therefore, it can only be opened with a key. Copper locks, padlocks, and different locks are paired with different keys. With the rapid development of science and technology, mechanical locks also have a long-term development trend. Contemporary mechanical locks have a history of more than 100 years. The anti-theft lock cylinder of the glass display cabinet has added marbles of different lengths, and the appearance design needs to be opened with a key of the corresponding tooth type. After that, the development trend came to combination padlocks, magnetic locks, electric control locks, and laser locks. On the basis of the traditional key, one or more login passwords are added, different electromagnetic fields, different light and electromagnetic waves, and different images. Such as fingerprint recognition, eye fundus macular, etc.) to control the opening of the lock.

At present, locks have produced a huge family, and they have been continuously improved and upgraded, constantly showing its awesomeness to the world. In general, locks have fully played the role of "binding" in the social development of the history of human development, standardizing social behavior, defending our personal safety, and maintaining the stability of the times.