I found today a very clear guide on how barcodes work, so figured it was worth sharing. Although the video claims to explain ‘how barcodes work’ it should be remembered that this is simply a UPC A barcode, one of many different types. However the principle of checksum characters and how the computer/scanner reads the barcode is able to be applied generally.
The key parts which are worth remembering is how the computer works out which line of a barcode is black and which is light. It may appear obvious but many people struggling to read barcodes are actually just facing issues due to a low scanning resolution where the lines run into one another. Another point to remember is that the checksum is only a ‘check’ and can still return a seemingly correct result when it is not correct. Therefore the inclusion of a checksum character is no replacement for good quality barcodes.
Let me know if you have any further questions about 1D Barcodes or checkout our knowledge base for barcode specifications.