by Ingrid Wu
Most of us have probably encountered an indefinite amount of barcodes in our day-to-day lives. A barcode itself is very simple: a series of parallel black lines and white spaces of varying widths. We’ve also all seen how it is used: the cashier scans the code and the details immediately pop up on the screen. These simple strings of characters can designate all types of information. Although this information was rather logical, I’ve never understood entirely how it stores code, and how it can transmit code. Everytime I purchase something, I interact with a barcode, never really giving them much notice. As a result, I decided to do further research to delve into the subject.
Two common types of barcodes
A barcode is a type of code printed on virtually any retail product to aid with identifying a particular item. There are two main types of barcodes: UPC (Universal Product Code) also known as the EAN-13 system, and the QR system, which stands for “quick response.”
1. EAN-13 system
The EAN-13 system, also called the linear barcode or UPC, is essentially one of the types of systems for embedding information. The bar code itself is simple: a series of black and white stripes, which resemble zebra stripes, of varying width. When it is scanned by a rapidly moving laser, a sensor detects the alternating pattern of black and white. The differences of widths are then translated into numbers. All of the information is essentially contained in a 13-digit code. Each digit from 0 to 9 has its own unique sequence of bars and spaces, with each digit separated by 7 bars. For instance, the number 6 has 2 white spaces and 5 black bars its sequence. In total, there are 95 small bars which make up the entire barcode.
What do the numbers mean?
The EAN-13 uses a standard system to group the different characters in the 13-digit number. The first two digits of a code identifies the country of production. To illustrate this, the digits 00 to 13 represent USA and Canada. The next five numbers determine the manufacturer identification number. The second set of five numbers represents the the product item code.
The last digit represents the modulo check character. The check digit is essentially another form of error checking, After the computer scans the barcode, it performs some calculations and determines a check digit to ensure it is the right number. The computer counts the number of white bars and the number of black bars. Theses two numbers must be equal to each other, and when the check digit is added, the total number of bars should equal 95.
Barcode generation and identification
One can generate a barcode by simply using computer software programs. First, we must consider the symbology of the barcode. In other words, if the barcode is 2-D or linear. Once the symbology is established, a user must identify in which environment the barcode is being used, as well as application compatibility. Following this procedure, the barcode must follow a specific font and formatting, so that it will be scannable. Often times, companies will obtain a GS1 company prefix, allowing companies to obtain identification keys for trade items such as units, assets and coupons. A barcode can be generated using computed-aided programs, companies tie these barcodes to products in the inventory or point-of-sale systems.
Barcode technology processes are used in business processes, and the procedures are automated to reduce human error and increase productivity. Take a look around! Wherever you’re at, there are thousands of barcodes lying around, whether it’s on a fruit, a food or beverage item, or on a mailpiece. After all, barcodes aren’t just random combinations of bars and white spaces, as they appear to be!
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