Saturday, May 22, 2010
Please note: The following article refers to the purchase of commercial barcodes. Barcodes can be printed 'in-house' by a business for their own internal use without having to purchase the barcodes.
Have you ever wondered how a bar code works? How does the scanner know what price to charge? Who decides what bar codes go on what products?
The bar code is called a Universal Product Code, or UPC. The first use for UPC codes was to label and keep track of railroad cars, but because the labels on the cars became dirty, the scanners couldn’t read them very well, and the system was set aside. Later it was returned to for better tracking of grocery product inventory, and to speed up the checkout process. They are now used in almost every major store.
The bar code is a representation of machine readable information. The first 6 digits are the product manufacturer’s identification. A company that wants to use bar codes has to apply for permission from the Uniform Code Council Company. They pay an annual fee for the use of the system. They are then assigned an identification number.
The next five digits of the bar code is the assigned item number. A person at the Universal Code Council Company, called the UPC coordinator, assigns numbers to items the manufacturer wants to bar code. This person also retires codes from products that are no longer sold. Every item needs to have its own number, and the UPC Coordinator has to keep them all straight.
The last digit in the code is a number that lets the scanner know if the bar code has been read correctly, or even if the bar code is scanned upside down. This number is the sum of a special math equation that the scanner performs when it reads the bar code. If the equation is wrong, the product needs to be rescanned. Sometimes, on a small item, the excess zeros are left off by a special configuration to save space. These are called suppressed zeros.
There is no actual price information in the bar code. Every store that uses bar coding has a central Point of Sale, or POS, computer that stores the bar codes for all items in the store and the accompanying information and prices. The scanner communicates with this computer to access this information. Not having the information on the actual bar code allows the store to change the price information when they need to all in one place as opposed to changing it on every individual item.
Have you ever wondered how a bar code works? How does the scanner know what price to charge? Who decides what bar codes go on what products?
The bar code is called a Universal Product Code, or UPC. The first use for UPC codes was to label and keep track of railroad cars, but because the labels on the cars became dirty, the scanners couldn’t read them very well, and the system was set aside. Later it was returned to for better tracking of grocery product inventory, and to speed up the checkout process. They are now used in almost every major store.
The bar code is a representation of machine readable information. The first 6 digits are the product manufacturer’s identification. A company that wants to use bar codes has to apply for permission from the Uniform Code Council Company. They pay an annual fee for the use of the system. They are then assigned an identification number.
The next five digits of the bar code is the assigned item number. A person at the Universal Code Council Company, called the UPC coordinator, assigns numbers to items the manufacturer wants to bar code. This person also retires codes from products that are no longer sold. Every item needs to have its own number, and the UPC Coordinator has to keep them all straight.
The last digit in the code is a number that lets the scanner know if the bar code has been read correctly, or even if the bar code is scanned upside down. This number is the sum of a special math equation that the scanner performs when it reads the bar code. If the equation is wrong, the product needs to be rescanned. Sometimes, on a small item, the excess zeros are left off by a special configuration to save space. These are called suppressed zeros.
There is no actual price information in the bar code. Every store that uses bar coding has a central Point of Sale, or POS, computer that stores the bar codes for all items in the store and the accompanying information and prices. The scanner communicates with this computer to access this information. Not having the information on the actual bar code allows the store to change the price information when they need to all in one place as opposed to changing it on every individual item.
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