The invention of QR code was originally applied to catering industry A, automobile industry B, cit industry D and aerospace industry.

QR(Quick Response) code, also known as two-dimensional bar code, is a black-and-white figure with specific geometry and distributed on the plane (two-dimensional direction) according to certain rules, and it is a key for all information and data. In modern business activities, it can be widely used, such as product anti-counterfeiting/traceability, advertisement push, website link, data download, commodity trading, positioning/navigation, electronic certificate, vehicle management, information transmission, business card exchange, wifi*** enjoyment and so on. Initially, food and corresponding automatic identification equipment were represented by codes. Bar code first appeared in 1940s, but its application and development was around 1970s. At present, bar code technology has been widely used in all countries and regions of the world, and is rapidly spreading to all parts of the world. The application fields are more and more extensive and gradually penetrate into many technical fields. As early as the 1940s, two engineers, jo woodland and Berny Searwar, began to study how to use codes and corresponding automatic identification devices to represent food items, and obtained American patents in 1949. This mode is very similar to a miniature archery target, which is called "bull's-eye" code. The concentric circles of the target are drawn into rings by circles and spaces. In principle, the "bull's-eye" code is very similar to the later bar code, but unfortunately, the technology and commodity economy at that time could not print this code. However, 20 years later, jo woodland became the founder of UPC code as an engineer of IBM. Several inventors represented by Girard Fe- -ssel applied for a patent in 1959, describing that every number from 0 to 9 can be composed of seven parallel bars. But this code makes the machine difficult to read, and it is not convenient for people to read. However, this idea did promote the emergence and development of bar codes later. Soon, E·F· brinker applied for another patent, which was to mark the bar code on the tram. The system invented by Searwar in the late 1960s was adopted by the North American railway system. These two items can be said to be the earliest application of bar code technology.