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Barcodes (条形码) aren’t given much thought by the majority

of consumers, but these codes were fairly recently applied in a working

fashion in 1970.

A small food store owner decided one day that keeping records of the inventory (存货) of his stock and the associated prices were an extremely laborious process, and so, in 1948, he contacted The Drexel Institute of Technology in a bid(投标) to work towards a solution. Bernard Silver rose to the challenge and set out to study the problem, and began working on a solution involving an automatic way of keeping track of items that had been sold. Silver and a group of students from the institute realized their answer in the form of ultraviolet light (紫外线), ink and a scanner.

The system worked at first, but possessed some negatives. It was unbelievably costly to carry out on a large scale and the system was also unstable. If the invention was to become commonplace (寻常的事) in grocery stores, these two problems had to be solved.

The patent for the barcode system was filed(申请)by Silver and one of his students, Woodland. The patent was not granted immediately; in fact it took three years for the patent agency to admit their invention patent for the barcode, occurring on 7th October, 1952.

Despite the patent being issued, the system was still not welcomed by the majority of store owners. It was not until 1966 that the system began moving its way into more and more grocery stores. This system was soon criticised, as there was no central mechanism for controlling uniformly (一致的)coded items. In 1970, Logicorn developed the Universal Grocery Products Identification code (UGPIC), soon shortened to Universal Identification Number (UPC). It was Marsh’s superstore, in Troy, which was the very first store to install this complex barcode reading system, and its popularity has soared (升温) ever since, and is obviously now commonplace in all types of stores worldwide.