A Little Bit About Barcodes
Most people think of a barcode as “a machine-readable code in the form of numbers and a pattern of parallel lines of varying widths, printed on and identifying a product”(*) or simply put, “a white box with black vertical lines printed on packaging or shipping labels.” However, there are two general types of barcodes: 1D or one-dimensional and 2D or two-dimensional. These distinct classes of barcode look different and can encode different data.
1D barcodes are linear, like the UPC or code128, and fit into the above definition as being a series of variable-width lines and alphanumeric characters that encode a specific and limited amount of data.
2D barcodes, such as QR codes or Data Matrix, don’t use parallel lines, rather they use patterns of squares, dots or other shapes to encode a greater amount of data, but beyond alphanumeric characters can also encode images, links, and other binary information.
As a rule, most print shops will recommend a few things to boost scan success for barcodes, such as high contrast and a minimum size. The best results are achieved when barcodes are printed with black ink on a white background and are large enough to ensure that the lines won’t bleed together if there is some ink gain during printing.
There are lots of different barcodes out there but for the purposes of this article, let’s focus on a few that are commonly printed on custom labels.
One of the oldest barcodes, commonly used for part identification found in automotive, healthcare and electronics. It is lineal, uses alphanumeric code, can be read by most barcode readers, low to medium information density, limited by the length availability on label. If space is a factor, consider code128.
Derived from the ASCII 128-character set (0-9), (A-Z), (a-z) and some special characters. Compact with high information density, used for sophisticated packaging, shipping and tracing applications, such as in hospitals.
Interleaved 2 of 5
Commonly used in warehouses for distribution, manufacturing and inventory control, these barcodes are only encoded with numeric values and must use pairs of numbers. Accurate printing is imperative for code 2 of 5 but then they possess high reliability scanning.
“Universal Product Code” is found on nearly every retail product to enable stores quick identification for receipt printing and inventory tracking. A manufacturer needs to secure a UPC number and then they will be assigned a unique company number that they can combine with their multitude of product numbers.
QR codes or “Quick Response” codes are a two-dimensional barcode and have grown greatly in popularity due to their marketing applications. These codes can be quickly read by smartphones and link the user to websites, promotions, surveys or other web-based information thereby making them a powerful tool to expand consumer awareness. They also have security, tracking and cataloging uses as well.