Most of us are familiar with the labels on just about everything we buy called barcodes. But we take for granted the technology and the complexities of these barcodes. There is a system called symbology that makes barcodes function the way that they do. So what exactly is barcode symbology? Symbology is a system of encoding data. This system is created so that an object such as a scanner can then decode the data from the barcode. When you look at a barcode, you may notice that some look different than others. There are generally two categories of barcode symbology: discrete and continuous. The discrete form of symbology simply means that each character individually on the barcode can be decoded without working with the other characters on the same barcode. In other words, each separate character is decoded by the scanner or other device by itself. Continuous barcode symbology means that every single character on an individual barcode must be read together. If they are separated, the barcode becomes invalid. These types of barcodes are used for more important types of things such as human identification (driver's licenses, etc).
Another aspect of barcode symbology is the width and lengths of the many bars seen on the barcode. The term two-width symbology refers to the barcodes that have only two different bar sizes in either a wide or a narrow width. They can be in any combination of widths (in other words, in any order, but only narrow and wide). Multiple-width symbology, however, allows for three different widths of bars versus only two (1x, 2x, 3x). This allows for a more difficult encoding and decoding process, and again, allows for more accuracy and precision when marking and keeping track of inventory. Another way to think of barcode symbology is to equate it to a language. Every part of a barcode has a special meaning, which is why it is encoded to be interpreted by a computer. The basic principals and foundations of barcode symbology are the symbol set, density, readability, setup, and acceptance. Acceptance basically means that the barcode should be compatible with another company's scanners or database so that it can be easily read. Learning about what each principal means can make interpreting various barcodes much easier.
The UPC code is the most commonly used form of barcode symbology. This is typically used for items in grocery stores or smaller general merchandise stores. There are other terms for various symbologies used in barcode encoding as well. Some other examples are Codabar, EAN/JAN, Zip + 4/Postdirect (usually used by the United States Postal Service), and 2-Dimensional barcode symbology. All of these are important for tracking, logging, and maintaining accurate inventory. Since technology has become much more developed over the last few decades, the science of barcode symbology had to adapt. No longer are barcodes only used for grocery items. Today, the barcode can be seen almost everywhere on millions of items. With the new processes developed by varying symbologies, barcodes will remain an important part of our lives.