Where would we be without the humble bar code? We would certainly be spending more time in the supermarket checkout line. Pretty much every retail product you buy these days has a bar code. This bar code is known as a UPC code and looks pretty much like the one above. I have written before about how you can obtain a UPC code, but here I am just covering the basics of the bar codes themselves.
The UPC (Universal Product Code) bar code is a 12 digit code used by manufacturers to identify themselves and their products. The first six digits are the manufacturer's number provided to them by the Uniform Code Council (now known as the GS1 Symbology Committee). The next five digits are the manufacturer's item number that is allocated to a specific product. Every single product a manufacturer sells including the same item of a different size carries its own unique five digit number. The last number is a calculated check digit that enables the scanner to verify that the number is correct.
Here at Lightning Labels we create UPC bar codes pretty much every day. We use the inbuilt functionality in CorelDraw to create a graphic file of the UPC, but you can also use a software package from such vendors as IDAutomation or Hallogram.
While most of the bar codes we do are UPC there are other bar codes we produce from time to time. The bar code above is what is known as a Code 39 (also known as Code 3 of 9). It is often used on name badges, to track inventory, and the post office uses it to track packages. You can encode letters and numbers, and often you will encode a start and stop character at the beginning and end of the data. If you want to keep track of your products internally this is a good bar code to use - we have a couple of customers who regularly request variable bar code labels using Code 39.
The bar code above is a Code 128 bar code. It is what is known as a high density symbology that encodes numbers, symbols, upper and lower case text as well as returns and tabs. It is known as high density because it takes up less space than other bar codes (such as code 39) as you can see here. To create a bar code 128 you will need a start character, a stop character, and a checksum character. We use the Code 128 Font Advantage Package from IDAutomation to create these bar codes - it comes with the Code 128 fonts and an Excel macro that you can use to generate the correct start, stop and checksum characters.
The world of bar codes can be quite complex and is changing rapidly. But these three bar codes are the most common - and the UPC bar code is so ubiquitous it will be around for a long time to come.